ADVANCING INNOVATION TOWARDS BREAKTHROUGH

CANCER THERAPIES

November 2019

LISTED EURONEXT Paris NASDAQ Copenhagen

EPA ONXEO

IMPORTANT You must read the following before continuing In accessing this document you agree to be bound by the following terms and conditions

This document has been prepared by Onxeo SA (together with its subsidiaries the Group) and is for information purposes only The content of this document is provisional and for information purposes only and isnot to be construed as providing investment advice The information statements and opinions contained in this document (the ldquoInformationrdquo) are provided as of the date of this document only and may be subject tosignificant changes at any time without notice Neither the Group nor its advisors nor any other person is under any obligation to update the Information Subject to applicable law none of the Company or its advisorsaccepts any responsibility whatsoever and makes no representation or warranty express or implied as to the fairness accuracy completeness or correctness of the Information The Information has not been subjectto independent verification and is qualified in its entirety by the business financial and other information that the Group is required to publish in accordance with the rules regulations and practices applicable tocompanies listed on Euronext Paris including in particular the risk factors in the Companyrsquos latest Registration Document andor its actualization filed with the French Financial Markets Authority (Autoriteacute des marcheacutesfinanciers) in any other periodic report and in any other press release which are available free of charge on the websites of the Group (wwwonxeocom) andor the AMF (wwwamf-franceorg)

This document contains information on the use of the Groups products and its competitive position Some of the Information is from third parties While this third party information has been obtained from sourcesbelieved to be reliable there is no guarantee of the accuracy or completeness of such data In addition certain of the industry and market data comes from the Groups own internal research and estimates based onthe knowledge and experience of the Groups management While the Group believes that such research and estimates are reasonable and reliable they and their underlying methodology and assumptions have notbeen verified by any independent source for accuracy or completeness and are subject to change without notice Accordingly undue reliance should not be placed on any of the industry market or competitiveposition data contained in the Information

The Information is not directed to or intended for distribution to or use by any person or entity that is a citizen or resident of or located in any locality state country or other jurisdiction where such distribution oruse would be contrary to law or regulation or which would require any registration or licensing within such jurisdiction The Information does not constitute or form part of and should not be construed as an offer orthe solicitation of an offer to subscribe for or purchase of any securities No public offering of securities may be conducted in France prior to the delivery by the French Financial Markets Authority of a visa on aprospectus that complies with the provisions of Directive 200371CE as amended This document is for information purposes only and does not constitute an offering document or an offer of securities to the public inthe United Kingdom to which section 85 of the Financial Services and Markets Act 2000 of the United Kingdom applies Securities may not be offered or sold in the United States absent registration under the USSecurities Act of 1933 as amended or an exemption from registration thereunder

This document contains certain forward-looking statements All statements in this document other than statements of historical fact are or may be deemed to be forward looking statements These statements are notguarantees of the Groups future performance These forward-looking statements relate without limitation to the Groups future prospects developments marketing strategy regulatory calendar clinical milestonesassumptions and hypothesis clinical development approach and financial requirements and are based on analyses of earnings forecasts and estimates of amounts not yet determinable and other financial and non-financial information Forward-looking statements are subject to a variety of risks and uncertainties as they relate to future events and are dependent on circumstances that may or may not materialize in the futureForward-looking statements cannot under any circumstance be construed as a guarantee of the Groups future performance as to strategic regulatory financial or other matters and the Grouprsquos actual performanceincluding its financial position results and cash flow as well as the trends in the sector in which the Group operates may differ materially from those proposed or reflected in the forward-looking statements containedin this document Even if the Grouprsquos performance including its financial position results cash-flows and developments in the sector in which the Group operates were to conform to the forward-looking statementscontained in this document such results or developments cannot be construed as a reliable indication of the Groups future results or developments The Group expressly declines any obligation to update or toconfirm projections or estimates made by analysts or to make public any correction to any prospective information in order to reflect an event or circumstance that may occur after the date of this document

Important Information

3Developing disruptive therapies in the field of DNA Damage Response (DDR) to address unmet needs in oncology

NEXT KEY MILESTONES FUNDEDFinancial visibility to Q3 2020 supports strategic plan to deliver near-term clinical inflection points

STRONG SCIENTIFIC TRANSLATIONAL amp CLINICAL CAPACITYA highly skilled amp experienced team of 35 with in-house capabilities to lead compounds from preclinical to proof-of-concept in man

DIFFERENTIATED SCIENCE IN DNA DAMAGE RESPONSE

PlatONtrade proprietary chemistry platform of decoy agonist oligonucleotides generatingnew compoundsAsiDNAtrade lead candidate at clinical stage first-in-class agonist showing unique anti-tumoral properties

A WELL-DEFINED BUSINESS MODELCreate value in bringing product candidates to inflection points and monetizing these assets to generate revenues

LISTED EURONEXT Paris NASDAQ Copenhagen

EPA ONXEO

November 2019

4

FRANCOISE BONO (PHD) CSO(Sanofi Evotec)

OLIVIER DE BEAUMONT (MD) CMO(Aventis Quintiles Stallergenes Greer)

NICOLAS FELLMAN CFO(Pfizer Ernst amp Young)

PHILIPPE MAITRE EVP CBDO(Aventis PPD mAbRx)

Experienced management team and board of directors

JUDITH GRECIETCEO

DANIEgraveLE GUYOT-CAPARROSChairperson of the Board

Chairperson of Audit committeeSenior Advisor Deloitte Consulting

CHRISTINE GARNIERCo-Founder of AEC Partners Strategic consulting

JEAN-PIERRE BIZZARIFormer EVP Clinical Oncology Celgene

THOMAS HOFSTAETTERFormer head of VaxInnate Corp

Chairman of BD committee

JEAN-PIERRE KINETImmunologist

Harvard Medical School

NICOLAS TREBOUTArepresenting Financiegravere de la Montagne

ELVIRA SANZFormer President Pfizer

Spain amp Portugal

November 2019

JUDITH GRECIET (PHARMD)CEO(formerly Pharmacia Wyeth Eisai)

5

Programs OPTIMIZATION PRECLINICAL PHASE I PHASE Ib PHASE II PHASE III MARKET

platONtrade Proprietary Platform of Decoy Oligonucleotides

OX401Next-gen PARPi + STING pathway activation

AsiDNAtrade IT + radiotherapy

AsiDNAtrade IV

AsiDNAtrade IV + chemotherapy

AsiDNAtrade IV + PARPi

Beleodaqreg2

belinostat + platONtrade

Cutting-edge RampD pipeline with unique mechanisms of action in DDR

DRIIV -1b

DRIIV study in solid tumors

GENERATION OF DISRUPTIVE COMPOUNDS TARGETING DNA-BINDING FUNCTIONS

Epig

enet

ics

DN

A D

amag

e

Re

spo

nse

1 IT intratumoral ndash IV intravenous 2 Beleodaqreg commercial brand name of belinostat (IV form) in the US in rr PTCL3 4 PTCL Peripheral T-cell lymphoma ndash a rare form of blood cancer

4 Commercialized in the US by Onxeorsquos partner under a conditional market authorization from the FDA for the use of Beleodaqreg in the treatment of 2nd line PTCL

DRIIM study in metastatic melanoma

2nd line PTCL3 US4

November 2019Completed or ongoing Planned short-term Legend

DD

R

+ IO

Solid tumors

ASIDNAtrade

7AsiDNAtrade is a first-in-class product in DNA Damage Response

November 2019

A synthetic cholesterol-oligonucleotide conjugate forming an intramolecular hairpin 32-base pair double helix

5rsquo

3rsquo

3rsquo

5rsquo

Genomic DNA length optimized to bind and activate DNA-PK and PARP signaling enzymes

Phosphorothioate substitutions at the 5rsquo and 3rsquo ends to prevent degradation1

Double-stranded 32 bp DNA is tethered with a loop to prevent disassociation1

Sequence not specific chosen to be non-homologous and not immunogenic (CpG-free)

Active 32 bp DNA duplex Cholesterol

Loop

1 Quanz M et al PLoS ONE 2009 4(7) doi 101371journalpone00062982 Berthault N et al Cancer Gene Therapy (2011) 1-12 doi 101038cgt20113

Efficient tumoral and nuclear uptake of the DNA is mediated via a covalently linked cholesterol molecule2

Patent Protection (Composition of

Matter on AsiDNAtrade amp related compounds)

until 2031

Extendable to 2036 with SPC amp PTE

Combinationpatents up to 2038

and more

IP

8AsiDNAtrade is the only decoy agonist in development that disrupts and exhausts the tumor DNA Damage Response

November 2019

Actual tumor DNA damage is not repaired and accumulates cancer cells die when dividing with a damaged DNA

AsiDNAtrade is not active in healthy cells which stop dividing until the false alarm disappears

AsiDNAtrade mimics DNA breaks in the tumor cell hyperactivates and then binds the proteins needed for the DDR cascade of cellular events (sensing signaling and repairing) diverting the DDR proteins away from the true damage 123

AsiDNAtrade is a multi-target DDRi acting upstream of the DDR cascade on multiple repair pathways and active regardless of genetic mutations without inducing resistance in tumor cells

AsiDNAtrade mimics DNA breaks in the tumor cell sends false alarms (decoy mechanism) then binds and activates key proteins of the DNA Damage Response

This sustained artificial DNA damage signaling (agonist effect) leads to exhaustion of the tumor DNA repair machinery

1

1 Quanz M et al Clin Cancer Res 2009 151308-1316 2 Quanz M et al PLoS ONE 2009 4(7) doi 101371 journalpone0006298 3 Jdey W et al Oin Can Res 201622DOI 101158 1078-0432CCR-16-1193

2

3

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

IMPORTANT You must read the following before continuing In accessing this document you agree to be bound by the following terms and conditions

This document has been prepared by Onxeo SA (together with its subsidiaries the Group) and is for information purposes only The content of this document is provisional and for information purposes only and isnot to be construed as providing investment advice The information statements and opinions contained in this document (the ldquoInformationrdquo) are provided as of the date of this document only and may be subject tosignificant changes at any time without notice Neither the Group nor its advisors nor any other person is under any obligation to update the Information Subject to applicable law none of the Company or its advisorsaccepts any responsibility whatsoever and makes no representation or warranty express or implied as to the fairness accuracy completeness or correctness of the Information The Information has not been subjectto independent verification and is qualified in its entirety by the business financial and other information that the Group is required to publish in accordance with the rules regulations and practices applicable tocompanies listed on Euronext Paris including in particular the risk factors in the Companyrsquos latest Registration Document andor its actualization filed with the French Financial Markets Authority (Autoriteacute des marcheacutesfinanciers) in any other periodic report and in any other press release which are available free of charge on the websites of the Group (wwwonxeocom) andor the AMF (wwwamf-franceorg)

This document contains information on the use of the Groups products and its competitive position Some of the Information is from third parties While this third party information has been obtained from sourcesbelieved to be reliable there is no guarantee of the accuracy or completeness of such data In addition certain of the industry and market data comes from the Groups own internal research and estimates based onthe knowledge and experience of the Groups management While the Group believes that such research and estimates are reasonable and reliable they and their underlying methodology and assumptions have notbeen verified by any independent source for accuracy or completeness and are subject to change without notice Accordingly undue reliance should not be placed on any of the industry market or competitiveposition data contained in the Information

The Information is not directed to or intended for distribution to or use by any person or entity that is a citizen or resident of or located in any locality state country or other jurisdiction where such distribution oruse would be contrary to law or regulation or which would require any registration or licensing within such jurisdiction The Information does not constitute or form part of and should not be construed as an offer orthe solicitation of an offer to subscribe for or purchase of any securities No public offering of securities may be conducted in France prior to the delivery by the French Financial Markets Authority of a visa on aprospectus that complies with the provisions of Directive 200371CE as amended This document is for information purposes only and does not constitute an offering document or an offer of securities to the public inthe United Kingdom to which section 85 of the Financial Services and Markets Act 2000 of the United Kingdom applies Securities may not be offered or sold in the United States absent registration under the USSecurities Act of 1933 as amended or an exemption from registration thereunder

This document contains certain forward-looking statements All statements in this document other than statements of historical fact are or may be deemed to be forward looking statements These statements are notguarantees of the Groups future performance These forward-looking statements relate without limitation to the Groups future prospects developments marketing strategy regulatory calendar clinical milestonesassumptions and hypothesis clinical development approach and financial requirements and are based on analyses of earnings forecasts and estimates of amounts not yet determinable and other financial and non-financial information Forward-looking statements are subject to a variety of risks and uncertainties as they relate to future events and are dependent on circumstances that may or may not materialize in the futureForward-looking statements cannot under any circumstance be construed as a guarantee of the Groups future performance as to strategic regulatory financial or other matters and the Grouprsquos actual performanceincluding its financial position results and cash flow as well as the trends in the sector in which the Group operates may differ materially from those proposed or reflected in the forward-looking statements containedin this document Even if the Grouprsquos performance including its financial position results cash-flows and developments in the sector in which the Group operates were to conform to the forward-looking statementscontained in this document such results or developments cannot be construed as a reliable indication of the Groups future results or developments The Group expressly declines any obligation to update or toconfirm projections or estimates made by analysts or to make public any correction to any prospective information in order to reflect an event or circumstance that may occur after the date of this document

Important Information

3Developing disruptive therapies in the field of DNA Damage Response (DDR) to address unmet needs in oncology

NEXT KEY MILESTONES FUNDEDFinancial visibility to Q3 2020 supports strategic plan to deliver near-term clinical inflection points

STRONG SCIENTIFIC TRANSLATIONAL amp CLINICAL CAPACITYA highly skilled amp experienced team of 35 with in-house capabilities to lead compounds from preclinical to proof-of-concept in man

DIFFERENTIATED SCIENCE IN DNA DAMAGE RESPONSE

PlatONtrade proprietary chemistry platform of decoy agonist oligonucleotides generatingnew compoundsAsiDNAtrade lead candidate at clinical stage first-in-class agonist showing unique anti-tumoral properties

A WELL-DEFINED BUSINESS MODELCreate value in bringing product candidates to inflection points and monetizing these assets to generate revenues

LISTED EURONEXT Paris NASDAQ Copenhagen

EPA ONXEO

November 2019

4

FRANCOISE BONO (PHD) CSO(Sanofi Evotec)

OLIVIER DE BEAUMONT (MD) CMO(Aventis Quintiles Stallergenes Greer)

NICOLAS FELLMAN CFO(Pfizer Ernst amp Young)

PHILIPPE MAITRE EVP CBDO(Aventis PPD mAbRx)

Experienced management team and board of directors

JUDITH GRECIETCEO

DANIEgraveLE GUYOT-CAPARROSChairperson of the Board

Chairperson of Audit committeeSenior Advisor Deloitte Consulting

CHRISTINE GARNIERCo-Founder of AEC Partners Strategic consulting

JEAN-PIERRE BIZZARIFormer EVP Clinical Oncology Celgene

THOMAS HOFSTAETTERFormer head of VaxInnate Corp

Chairman of BD committee

JEAN-PIERRE KINETImmunologist

Harvard Medical School

NICOLAS TREBOUTArepresenting Financiegravere de la Montagne

ELVIRA SANZFormer President Pfizer

Spain amp Portugal

November 2019

JUDITH GRECIET (PHARMD)CEO(formerly Pharmacia Wyeth Eisai)

5

Programs OPTIMIZATION PRECLINICAL PHASE I PHASE Ib PHASE II PHASE III MARKET

platONtrade Proprietary Platform of Decoy Oligonucleotides

OX401Next-gen PARPi + STING pathway activation

AsiDNAtrade IT + radiotherapy

AsiDNAtrade IV

AsiDNAtrade IV + chemotherapy

AsiDNAtrade IV + PARPi

Beleodaqreg2

belinostat + platONtrade

Cutting-edge RampD pipeline with unique mechanisms of action in DDR

DRIIV -1b

DRIIV study in solid tumors

GENERATION OF DISRUPTIVE COMPOUNDS TARGETING DNA-BINDING FUNCTIONS

Epig

enet

ics

DN

A D

amag

e

Re

spo

nse

1 IT intratumoral ndash IV intravenous 2 Beleodaqreg commercial brand name of belinostat (IV form) in the US in rr PTCL3 4 PTCL Peripheral T-cell lymphoma ndash a rare form of blood cancer

4 Commercialized in the US by Onxeorsquos partner under a conditional market authorization from the FDA for the use of Beleodaqreg in the treatment of 2nd line PTCL

DRIIM study in metastatic melanoma

2nd line PTCL3 US4

November 2019Completed or ongoing Planned short-term Legend

DD

R

+ IO

Solid tumors

ASIDNAtrade

7AsiDNAtrade is a first-in-class product in DNA Damage Response

November 2019

A synthetic cholesterol-oligonucleotide conjugate forming an intramolecular hairpin 32-base pair double helix

5rsquo

3rsquo

3rsquo

5rsquo

Genomic DNA length optimized to bind and activate DNA-PK and PARP signaling enzymes

Phosphorothioate substitutions at the 5rsquo and 3rsquo ends to prevent degradation1

Double-stranded 32 bp DNA is tethered with a loop to prevent disassociation1

Sequence not specific chosen to be non-homologous and not immunogenic (CpG-free)

Active 32 bp DNA duplex Cholesterol

Loop

1 Quanz M et al PLoS ONE 2009 4(7) doi 101371journalpone00062982 Berthault N et al Cancer Gene Therapy (2011) 1-12 doi 101038cgt20113

Efficient tumoral and nuclear uptake of the DNA is mediated via a covalently linked cholesterol molecule2

Patent Protection (Composition of

Matter on AsiDNAtrade amp related compounds)

until 2031

Extendable to 2036 with SPC amp PTE

Combinationpatents up to 2038

and more

IP

8AsiDNAtrade is the only decoy agonist in development that disrupts and exhausts the tumor DNA Damage Response

November 2019

Actual tumor DNA damage is not repaired and accumulates cancer cells die when dividing with a damaged DNA

AsiDNAtrade is not active in healthy cells which stop dividing until the false alarm disappears

AsiDNAtrade mimics DNA breaks in the tumor cell hyperactivates and then binds the proteins needed for the DDR cascade of cellular events (sensing signaling and repairing) diverting the DDR proteins away from the true damage 123

AsiDNAtrade is a multi-target DDRi acting upstream of the DDR cascade on multiple repair pathways and active regardless of genetic mutations without inducing resistance in tumor cells

AsiDNAtrade mimics DNA breaks in the tumor cell sends false alarms (decoy mechanism) then binds and activates key proteins of the DNA Damage Response

This sustained artificial DNA damage signaling (agonist effect) leads to exhaustion of the tumor DNA repair machinery

1

1 Quanz M et al Clin Cancer Res 2009 151308-1316 2 Quanz M et al PLoS ONE 2009 4(7) doi 101371 journalpone0006298 3 Jdey W et al Oin Can Res 201622DOI 101158 1078-0432CCR-16-1193

2

3

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

3Developing disruptive therapies in the field of DNA Damage Response (DDR) to address unmet needs in oncology

NEXT KEY MILESTONES FUNDEDFinancial visibility to Q3 2020 supports strategic plan to deliver near-term clinical inflection points

STRONG SCIENTIFIC TRANSLATIONAL amp CLINICAL CAPACITYA highly skilled amp experienced team of 35 with in-house capabilities to lead compounds from preclinical to proof-of-concept in man

DIFFERENTIATED SCIENCE IN DNA DAMAGE RESPONSE

PlatONtrade proprietary chemistry platform of decoy agonist oligonucleotides generatingnew compoundsAsiDNAtrade lead candidate at clinical stage first-in-class agonist showing unique anti-tumoral properties

A WELL-DEFINED BUSINESS MODELCreate value in bringing product candidates to inflection points and monetizing these assets to generate revenues

LISTED EURONEXT Paris NASDAQ Copenhagen

EPA ONXEO

November 2019

4

FRANCOISE BONO (PHD) CSO(Sanofi Evotec)

OLIVIER DE BEAUMONT (MD) CMO(Aventis Quintiles Stallergenes Greer)

NICOLAS FELLMAN CFO(Pfizer Ernst amp Young)

PHILIPPE MAITRE EVP CBDO(Aventis PPD mAbRx)

Experienced management team and board of directors

JUDITH GRECIETCEO

DANIEgraveLE GUYOT-CAPARROSChairperson of the Board

Chairperson of Audit committeeSenior Advisor Deloitte Consulting

CHRISTINE GARNIERCo-Founder of AEC Partners Strategic consulting

JEAN-PIERRE BIZZARIFormer EVP Clinical Oncology Celgene

THOMAS HOFSTAETTERFormer head of VaxInnate Corp

Chairman of BD committee

JEAN-PIERRE KINETImmunologist

Harvard Medical School

NICOLAS TREBOUTArepresenting Financiegravere de la Montagne

ELVIRA SANZFormer President Pfizer

Spain amp Portugal

November 2019

JUDITH GRECIET (PHARMD)CEO(formerly Pharmacia Wyeth Eisai)

5

Programs OPTIMIZATION PRECLINICAL PHASE I PHASE Ib PHASE II PHASE III MARKET

platONtrade Proprietary Platform of Decoy Oligonucleotides

OX401Next-gen PARPi + STING pathway activation

AsiDNAtrade IT + radiotherapy

AsiDNAtrade IV

AsiDNAtrade IV + chemotherapy

AsiDNAtrade IV + PARPi

Beleodaqreg2

belinostat + platONtrade

Cutting-edge RampD pipeline with unique mechanisms of action in DDR

DRIIV -1b

DRIIV study in solid tumors

GENERATION OF DISRUPTIVE COMPOUNDS TARGETING DNA-BINDING FUNCTIONS

Epig

enet

ics

DN

A D

amag

e

Re

spo

nse

1 IT intratumoral ndash IV intravenous 2 Beleodaqreg commercial brand name of belinostat (IV form) in the US in rr PTCL3 4 PTCL Peripheral T-cell lymphoma ndash a rare form of blood cancer

4 Commercialized in the US by Onxeorsquos partner under a conditional market authorization from the FDA for the use of Beleodaqreg in the treatment of 2nd line PTCL

DRIIM study in metastatic melanoma

2nd line PTCL3 US4

November 2019Completed or ongoing Planned short-term Legend

DD

R

+ IO

Solid tumors

ASIDNAtrade

7AsiDNAtrade is a first-in-class product in DNA Damage Response

November 2019

A synthetic cholesterol-oligonucleotide conjugate forming an intramolecular hairpin 32-base pair double helix

5rsquo

3rsquo

3rsquo

5rsquo

Genomic DNA length optimized to bind and activate DNA-PK and PARP signaling enzymes

Phosphorothioate substitutions at the 5rsquo and 3rsquo ends to prevent degradation1

Double-stranded 32 bp DNA is tethered with a loop to prevent disassociation1

Sequence not specific chosen to be non-homologous and not immunogenic (CpG-free)

Active 32 bp DNA duplex Cholesterol

Loop

1 Quanz M et al PLoS ONE 2009 4(7) doi 101371journalpone00062982 Berthault N et al Cancer Gene Therapy (2011) 1-12 doi 101038cgt20113

Efficient tumoral and nuclear uptake of the DNA is mediated via a covalently linked cholesterol molecule2

Patent Protection (Composition of

Matter on AsiDNAtrade amp related compounds)

until 2031

Extendable to 2036 with SPC amp PTE

Combinationpatents up to 2038

and more

IP

8AsiDNAtrade is the only decoy agonist in development that disrupts and exhausts the tumor DNA Damage Response

November 2019

Actual tumor DNA damage is not repaired and accumulates cancer cells die when dividing with a damaged DNA

AsiDNAtrade is not active in healthy cells which stop dividing until the false alarm disappears

AsiDNAtrade mimics DNA breaks in the tumor cell hyperactivates and then binds the proteins needed for the DDR cascade of cellular events (sensing signaling and repairing) diverting the DDR proteins away from the true damage 123

AsiDNAtrade is a multi-target DDRi acting upstream of the DDR cascade on multiple repair pathways and active regardless of genetic mutations without inducing resistance in tumor cells

AsiDNAtrade mimics DNA breaks in the tumor cell sends false alarms (decoy mechanism) then binds and activates key proteins of the DNA Damage Response

This sustained artificial DNA damage signaling (agonist effect) leads to exhaustion of the tumor DNA repair machinery

1

1 Quanz M et al Clin Cancer Res 2009 151308-1316 2 Quanz M et al PLoS ONE 2009 4(7) doi 101371 journalpone0006298 3 Jdey W et al Oin Can Res 201622DOI 101158 1078-0432CCR-16-1193

2

3

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

4

FRANCOISE BONO (PHD) CSO(Sanofi Evotec)

OLIVIER DE BEAUMONT (MD) CMO(Aventis Quintiles Stallergenes Greer)

NICOLAS FELLMAN CFO(Pfizer Ernst amp Young)

PHILIPPE MAITRE EVP CBDO(Aventis PPD mAbRx)

Experienced management team and board of directors

JUDITH GRECIETCEO

DANIEgraveLE GUYOT-CAPARROSChairperson of the Board

Chairperson of Audit committeeSenior Advisor Deloitte Consulting

CHRISTINE GARNIERCo-Founder of AEC Partners Strategic consulting

JEAN-PIERRE BIZZARIFormer EVP Clinical Oncology Celgene

THOMAS HOFSTAETTERFormer head of VaxInnate Corp

Chairman of BD committee

JEAN-PIERRE KINETImmunologist

Harvard Medical School

NICOLAS TREBOUTArepresenting Financiegravere de la Montagne

ELVIRA SANZFormer President Pfizer

Spain amp Portugal

November 2019

JUDITH GRECIET (PHARMD)CEO(formerly Pharmacia Wyeth Eisai)

5

Programs OPTIMIZATION PRECLINICAL PHASE I PHASE Ib PHASE II PHASE III MARKET

platONtrade Proprietary Platform of Decoy Oligonucleotides

OX401Next-gen PARPi + STING pathway activation

AsiDNAtrade IT + radiotherapy

AsiDNAtrade IV

AsiDNAtrade IV + chemotherapy

AsiDNAtrade IV + PARPi

Beleodaqreg2

belinostat + platONtrade

Cutting-edge RampD pipeline with unique mechanisms of action in DDR

DRIIV -1b

DRIIV study in solid tumors

GENERATION OF DISRUPTIVE COMPOUNDS TARGETING DNA-BINDING FUNCTIONS

Epig

enet

ics

DN

A D

amag

e

Re

spo

nse

1 IT intratumoral ndash IV intravenous 2 Beleodaqreg commercial brand name of belinostat (IV form) in the US in rr PTCL3 4 PTCL Peripheral T-cell lymphoma ndash a rare form of blood cancer

4 Commercialized in the US by Onxeorsquos partner under a conditional market authorization from the FDA for the use of Beleodaqreg in the treatment of 2nd line PTCL

DRIIM study in metastatic melanoma

2nd line PTCL3 US4

November 2019Completed or ongoing Planned short-term Legend

DD

R

+ IO

Solid tumors

ASIDNAtrade

7AsiDNAtrade is a first-in-class product in DNA Damage Response

November 2019

A synthetic cholesterol-oligonucleotide conjugate forming an intramolecular hairpin 32-base pair double helix

5rsquo

3rsquo

3rsquo

5rsquo

Genomic DNA length optimized to bind and activate DNA-PK and PARP signaling enzymes

Phosphorothioate substitutions at the 5rsquo and 3rsquo ends to prevent degradation1

Double-stranded 32 bp DNA is tethered with a loop to prevent disassociation1

Sequence not specific chosen to be non-homologous and not immunogenic (CpG-free)

Active 32 bp DNA duplex Cholesterol

Loop

1 Quanz M et al PLoS ONE 2009 4(7) doi 101371journalpone00062982 Berthault N et al Cancer Gene Therapy (2011) 1-12 doi 101038cgt20113

Efficient tumoral and nuclear uptake of the DNA is mediated via a covalently linked cholesterol molecule2

Patent Protection (Composition of

Matter on AsiDNAtrade amp related compounds)

until 2031

Extendable to 2036 with SPC amp PTE

Combinationpatents up to 2038

and more

IP

8AsiDNAtrade is the only decoy agonist in development that disrupts and exhausts the tumor DNA Damage Response

November 2019

Actual tumor DNA damage is not repaired and accumulates cancer cells die when dividing with a damaged DNA

AsiDNAtrade is not active in healthy cells which stop dividing until the false alarm disappears

AsiDNAtrade mimics DNA breaks in the tumor cell hyperactivates and then binds the proteins needed for the DDR cascade of cellular events (sensing signaling and repairing) diverting the DDR proteins away from the true damage 123

AsiDNAtrade is a multi-target DDRi acting upstream of the DDR cascade on multiple repair pathways and active regardless of genetic mutations without inducing resistance in tumor cells

AsiDNAtrade mimics DNA breaks in the tumor cell sends false alarms (decoy mechanism) then binds and activates key proteins of the DNA Damage Response

This sustained artificial DNA damage signaling (agonist effect) leads to exhaustion of the tumor DNA repair machinery

1

1 Quanz M et al Clin Cancer Res 2009 151308-1316 2 Quanz M et al PLoS ONE 2009 4(7) doi 101371 journalpone0006298 3 Jdey W et al Oin Can Res 201622DOI 101158 1078-0432CCR-16-1193

2

3

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

5

Programs OPTIMIZATION PRECLINICAL PHASE I PHASE Ib PHASE II PHASE III MARKET

platONtrade Proprietary Platform of Decoy Oligonucleotides

OX401Next-gen PARPi + STING pathway activation

AsiDNAtrade IT + radiotherapy

AsiDNAtrade IV

AsiDNAtrade IV + chemotherapy

AsiDNAtrade IV + PARPi

Beleodaqreg2

belinostat + platONtrade

Cutting-edge RampD pipeline with unique mechanisms of action in DDR

DRIIV -1b

DRIIV study in solid tumors

GENERATION OF DISRUPTIVE COMPOUNDS TARGETING DNA-BINDING FUNCTIONS

Epig

enet

ics

DN

A D

amag

e

Re

spo

nse

1 IT intratumoral ndash IV intravenous 2 Beleodaqreg commercial brand name of belinostat (IV form) in the US in rr PTCL3 4 PTCL Peripheral T-cell lymphoma ndash a rare form of blood cancer

4 Commercialized in the US by Onxeorsquos partner under a conditional market authorization from the FDA for the use of Beleodaqreg in the treatment of 2nd line PTCL

DRIIM study in metastatic melanoma

2nd line PTCL3 US4

November 2019Completed or ongoing Planned short-term Legend

DD

R

+ IO

Solid tumors

ASIDNAtrade

7AsiDNAtrade is a first-in-class product in DNA Damage Response

November 2019

A synthetic cholesterol-oligonucleotide conjugate forming an intramolecular hairpin 32-base pair double helix

5rsquo

3rsquo

3rsquo

5rsquo

Genomic DNA length optimized to bind and activate DNA-PK and PARP signaling enzymes

Phosphorothioate substitutions at the 5rsquo and 3rsquo ends to prevent degradation1

Double-stranded 32 bp DNA is tethered with a loop to prevent disassociation1

Sequence not specific chosen to be non-homologous and not immunogenic (CpG-free)

Active 32 bp DNA duplex Cholesterol

Loop

1 Quanz M et al PLoS ONE 2009 4(7) doi 101371journalpone00062982 Berthault N et al Cancer Gene Therapy (2011) 1-12 doi 101038cgt20113

Efficient tumoral and nuclear uptake of the DNA is mediated via a covalently linked cholesterol molecule2

Patent Protection (Composition of

Matter on AsiDNAtrade amp related compounds)

until 2031

Extendable to 2036 with SPC amp PTE

Combinationpatents up to 2038

and more

IP

8AsiDNAtrade is the only decoy agonist in development that disrupts and exhausts the tumor DNA Damage Response

November 2019

Actual tumor DNA damage is not repaired and accumulates cancer cells die when dividing with a damaged DNA

AsiDNAtrade is not active in healthy cells which stop dividing until the false alarm disappears

AsiDNAtrade mimics DNA breaks in the tumor cell hyperactivates and then binds the proteins needed for the DDR cascade of cellular events (sensing signaling and repairing) diverting the DDR proteins away from the true damage 123

AsiDNAtrade is a multi-target DDRi acting upstream of the DDR cascade on multiple repair pathways and active regardless of genetic mutations without inducing resistance in tumor cells

AsiDNAtrade mimics DNA breaks in the tumor cell sends false alarms (decoy mechanism) then binds and activates key proteins of the DNA Damage Response

This sustained artificial DNA damage signaling (agonist effect) leads to exhaustion of the tumor DNA repair machinery

1

1 Quanz M et al Clin Cancer Res 2009 151308-1316 2 Quanz M et al PLoS ONE 2009 4(7) doi 101371 journalpone0006298 3 Jdey W et al Oin Can Res 201622DOI 101158 1078-0432CCR-16-1193

2

3

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

ASIDNAtrade

7AsiDNAtrade is a first-in-class product in DNA Damage Response

November 2019

A synthetic cholesterol-oligonucleotide conjugate forming an intramolecular hairpin 32-base pair double helix

5rsquo

3rsquo

3rsquo

5rsquo

Genomic DNA length optimized to bind and activate DNA-PK and PARP signaling enzymes

Phosphorothioate substitutions at the 5rsquo and 3rsquo ends to prevent degradation1

Double-stranded 32 bp DNA is tethered with a loop to prevent disassociation1

Sequence not specific chosen to be non-homologous and not immunogenic (CpG-free)

Active 32 bp DNA duplex Cholesterol

Loop

1 Quanz M et al PLoS ONE 2009 4(7) doi 101371journalpone00062982 Berthault N et al Cancer Gene Therapy (2011) 1-12 doi 101038cgt20113

Efficient tumoral and nuclear uptake of the DNA is mediated via a covalently linked cholesterol molecule2

Patent Protection (Composition of

Matter on AsiDNAtrade amp related compounds)

until 2031

Extendable to 2036 with SPC amp PTE

Combinationpatents up to 2038

and more

IP

8AsiDNAtrade is the only decoy agonist in development that disrupts and exhausts the tumor DNA Damage Response

November 2019

Actual tumor DNA damage is not repaired and accumulates cancer cells die when dividing with a damaged DNA

AsiDNAtrade is not active in healthy cells which stop dividing until the false alarm disappears

AsiDNAtrade mimics DNA breaks in the tumor cell hyperactivates and then binds the proteins needed for the DDR cascade of cellular events (sensing signaling and repairing) diverting the DDR proteins away from the true damage 123

AsiDNAtrade is a multi-target DDRi acting upstream of the DDR cascade on multiple repair pathways and active regardless of genetic mutations without inducing resistance in tumor cells

AsiDNAtrade mimics DNA breaks in the tumor cell sends false alarms (decoy mechanism) then binds and activates key proteins of the DNA Damage Response

This sustained artificial DNA damage signaling (agonist effect) leads to exhaustion of the tumor DNA repair machinery

1

1 Quanz M et al Clin Cancer Res 2009 151308-1316 2 Quanz M et al PLoS ONE 2009 4(7) doi 101371 journalpone0006298 3 Jdey W et al Oin Can Res 201622DOI 101158 1078-0432CCR-16-1193

2

3

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

7AsiDNAtrade is a first-in-class product in DNA Damage Response

November 2019

A synthetic cholesterol-oligonucleotide conjugate forming an intramolecular hairpin 32-base pair double helix

5rsquo

3rsquo

3rsquo

5rsquo

Genomic DNA length optimized to bind and activate DNA-PK and PARP signaling enzymes

Phosphorothioate substitutions at the 5rsquo and 3rsquo ends to prevent degradation1

Double-stranded 32 bp DNA is tethered with a loop to prevent disassociation1

Sequence not specific chosen to be non-homologous and not immunogenic (CpG-free)

Active 32 bp DNA duplex Cholesterol

Loop

1 Quanz M et al PLoS ONE 2009 4(7) doi 101371journalpone00062982 Berthault N et al Cancer Gene Therapy (2011) 1-12 doi 101038cgt20113

Efficient tumoral and nuclear uptake of the DNA is mediated via a covalently linked cholesterol molecule2

Patent Protection (Composition of

Matter on AsiDNAtrade amp related compounds)

until 2031

Extendable to 2036 with SPC amp PTE

Combinationpatents up to 2038

and more

IP

8AsiDNAtrade is the only decoy agonist in development that disrupts and exhausts the tumor DNA Damage Response

November 2019

Actual tumor DNA damage is not repaired and accumulates cancer cells die when dividing with a damaged DNA

AsiDNAtrade is not active in healthy cells which stop dividing until the false alarm disappears

AsiDNAtrade mimics DNA breaks in the tumor cell hyperactivates and then binds the proteins needed for the DDR cascade of cellular events (sensing signaling and repairing) diverting the DDR proteins away from the true damage 123

AsiDNAtrade is a multi-target DDRi acting upstream of the DDR cascade on multiple repair pathways and active regardless of genetic mutations without inducing resistance in tumor cells

AsiDNAtrade mimics DNA breaks in the tumor cell sends false alarms (decoy mechanism) then binds and activates key proteins of the DNA Damage Response

This sustained artificial DNA damage signaling (agonist effect) leads to exhaustion of the tumor DNA repair machinery

1

1 Quanz M et al Clin Cancer Res 2009 151308-1316 2 Quanz M et al PLoS ONE 2009 4(7) doi 101371 journalpone0006298 3 Jdey W et al Oin Can Res 201622DOI 101158 1078-0432CCR-16-1193

2

3

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

8AsiDNAtrade is the only decoy agonist in development that disrupts and exhausts the tumor DNA Damage Response

November 2019

Actual tumor DNA damage is not repaired and accumulates cancer cells die when dividing with a damaged DNA

AsiDNAtrade is not active in healthy cells which stop dividing until the false alarm disappears

AsiDNAtrade mimics DNA breaks in the tumor cell hyperactivates and then binds the proteins needed for the DDR cascade of cellular events (sensing signaling and repairing) diverting the DDR proteins away from the true damage 123

AsiDNAtrade is a multi-target DDRi acting upstream of the DDR cascade on multiple repair pathways and active regardless of genetic mutations without inducing resistance in tumor cells

AsiDNAtrade mimics DNA breaks in the tumor cell sends false alarms (decoy mechanism) then binds and activates key proteins of the DNA Damage Response

This sustained artificial DNA damage signaling (agonist effect) leads to exhaustion of the tumor DNA repair machinery

1

1 Quanz M et al Clin Cancer Res 2009 151308-1316 2 Quanz M et al PLoS ONE 2009 4(7) doi 101371 journalpone0006298 3 Jdey W et al Oin Can Res 201622DOI 101158 1078-0432CCR-16-1193

2

3

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

9Wide therapeutic potential including different combinations and indications

November 2019

as a monotherapy

bull Selection of the best responding patients with stratification biomarkers

Up to 11 Million patients(incident population in 8MM)

with PARP inhibitors

bull Indications ovarian (ODD) breast HER2hellip

bull Expend PARPi use in both BRCAm amp BRCAwt

bull Abrogate resistance to PARPi

asymp 550000 patients1

(incident population in 8MM)

with radiotherapy

bull Indications sarcoma glioblastoma HampN lung cervix rectal cancers pediatric medulloblastoma

bull Radiosensitize and Synergy of efficacy

asymp 38 Million patients3

(incident population in 8MM)

HR Homologous recombination - OC Ovarian cancer - (TN)BC (Triple negative) Breast cancer - (N)SCLC (Non) Small cell lung cancer - HNC Head amp neck cancer - ODD Orphan Drug Designation - 1 OC + HER2 Neg BC (both BRCA wild-type) 2 OC + (N)SCLC + TNBC + HNC 3 All cancers (55 of incidence) Companyrsquos estimates in 8Major Markets (8MM) after GlobalData reports and Globocan 2018 data

with DNA-damaging chemotherapies

bull Indications OC (ODD) SCLC (ODD) NSCLC HNC (ODD) TNBC hellip

bull Synergy of efficacy with DNA breakers

asymp 13 Million patients2

(incident population in 8MM)

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

AsiDNAtrade

Robust preclinical amp translational data set supporting

clinical development

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

11AsiDNAtrade leads to cancer cell death and does not induce resistance

Treatment with AsiDNAtrade reduces cancer cells survival (1-30microM IC50)

In contrast to targeted therapies (eg PARPi) repeated treatment with AsiDNAtrade leads to sensitization to AsiDNAtrade and does not generate resistance

MDAMB231 ndash TNBC HR proficient(PARPi are ineffective on this cell line)

AsiDNA

BC227 ndash TNBC HR BRCA1 mutated

BC227

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

AsiDNA Talazoparib Olaparib

Surv

ival (

NT)

Source Onxeo data on fileNovember 2019

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

12AsiDNAtrade plus PARPi generates synergies in both HR deficient and proficient cancer cells and prevents resistance to PARPi

Expansion of PARPirsquos use to HR-proficient tumors combo shows the same efficacy in both HR deficient and proficient cancer cells

Synergistic efficacy combo leads to a rapid and complete inhibition of cancer cell survival not observed with PARPi alone

Prevention of the occurrence of PARPi-acquired resistance at low doses in several cancer cell lines

TNBCHR deficient(BC227)

SCLC(NCI-H446)

Olaparib 5 microM - Talazoparib 100nM - AsiDNAtrade 1microM Talazoparib 100nM ndash AsiDNAtrade 1microM

Source Onxeo data on fileNovember 2019

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

120

140

Olaparib Talazoparib

AsiDNA+Olaparib AsiDNA+Talazoparib

Surv

ival (

N

T)

1st cycle 2nd cycle 3rd cycle 4th cycle0

20

40

60

80

100

Talazoparib AsiDNA+Talazoparib

Surv

ival (

N

T)

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

13Combination of AsiDNAtrade with PARPi demonstrates synergy in HR proficient TNBC

AsiDNAtrade in combination with PARPi shows high efficacy in vivo in cancer cells non-sensitive to PARPi

Opportunity to expand PARPi indications to HR proficient tumors

NT olaparib AsiDNAtrade AsiDNAtrade + olaparib

Complete Response = 06 Complete Response = 28 Complete Response = 48 Complete Response = 57 0 25 50 71

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Source Onxeo data on fileNovember 2019

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

14Class-effect of the combination of AsiDNAtrade with PARPirsquos supportedby extensive preclinical testing

Both synergy and abrogation of resistance to treatment occur with all tested PARPi and regardless of the tumor type opening new opportunities for clinical applications

November 2019

Tumor model (cell lines primary tumors)

Treatment in combination Observed effect Reference

TNBC (MDA-MB-231xenograft mice model)

AsiDNAtrade + olaparib Complete response more than doubled Data on file

Resistant PDX ovarian model AsiDNAtrade + olaparib Synergy delaying tumor growth Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + olaparib or + talazoparib Resistance is prevented by co-treatment Data on file

Ovarian cancer AsiDNAtrade + niraparib Resistance is prevented by co-treatment Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Resistance is prevented by co-treatment Data on file

TNBC HR deficient (BC 227) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

SCLC (NCI-H446) AsiDNAtrade + talazoparib Rapid and complete inhibition of cancer cell survival Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + talazoparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + niraparib Synergistic antitumor effect Data on file

TNBC HR proficient (MDAMB231) AsiDNAtrade + olaparib Synergistic antitumor effect Data on file

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

15Combination of AsiDNAtrade with carboplatin shows synergy in resistant TNBC

0

100

200

300

400

500

600

700

800

900

1000

0 10 20 30 40 50 60 70 80 90 100

Mean

volu

mes (m

m3)

Time after treatment (days)

MDA-MB-231 (TNBC HR proficient tumor cells) xenograft in mice

Group I vehicle (Nacl 09)

Group II AsiDNA (IP)

Group III carboplatin (IP)

Group IV AsiDNA (IP) + carboplatin (IP)

Endpoint1500 mm3

d - XX graft

Week 7Week 4Week 1

Treatment Median survival(days)

Vehicle NaCl 09 15x IP (n 6) 77

Carboplatin 3x 50 mgkg IP (n 8) 88

AsiDNA 15x 5 mg IP (n 8) 128

AsiDNA 15x 5mg IP + carboplatin 3x 50mgkg IP (n 10)

175

Source Onxeo data on fileNovember 2019

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

16Data support increased efficacy of the combination of AsiDNAtrade with DNA-damaging agents in multiple in vivo models

Tumor model (cell lines primary tumors)

Treatment in combination Route of administration Reference

Breast cancer (BC227 BC173 MDA-MB468 MDA-MB231) AsiDNAtrade standalone

Intratumoral + Peritumoral Subcutaneous Intraperitoneal (MDA-MB231) Data on file

Breast cancer (MDAMB231 BC227) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Glioblastoma AsiDNAtrade + Radiotherapy Intratumoral Coquery et al 2012

Cutaneous melanoma AsiDNAtrade + RadiotherapySubcutaneous PeritumoralIntratumoral + subcutaneous Peritumoral

Schlegel et al 2012Biau et al 2014

Colorectal cancer AsiDNAtrade + RFA (hyperthermia) Intratumoral + subcutaneous Devun et al 2014

Colorectal Liver metastasis (HT29) AsiDNAtrade + 5FU + oxaliplatin Intraperitoneal Herath et al 2016

HCC (HepG2) AsiDNAtrade + doxorubicin Intraperitoneal Herath et al 2016

Head amp neck (Hep2) AsiDNAtrade + Radiotherapy Intratumoral Quanz et al 2009

Head amp Neck (Hep2) AsiDNAtrade + carboplatin Intraperitoneal Data on file

Lung cancer (TC-1) AsiDNAtrade + carboplatin or cisplatin Intraperitoneal Data on file

HCC (VX2 rabbit) AsiDNAtrade + TACE (Doxorubicin) Transarterial Herath et al 2016

November 2019

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

AsiDNAtrade

Clinical data and perspectives

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

18Successful DRIIM study in metastatic melanoma

Proof of concept established in completed DRIIM Phase I trial1 Intratumoral administration + radiotherapy in metastatic melanoma

Overall response rate = 593

Complete response = 303 (CR from low-dose radiotherapy alone less than 102)

Partial response = 293

Durable response (up to 12-month follow-up period)

Before treatment 90 days after treatment

1 Le Tourneau et al Br J Cancer 2016 May 24114(11)1199-205 2 Olivier et al Cancer 2007 Konefal et al Radiology 1987 3 of lesions

IT administration of AsiDNAtrade confirmed safety signal of efficacy systemic passage suggested

November 2019

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

19

PHASE I

Open-label 3+3 dose escalation 22 patients

2 European countries FR BE

5 centers Paris(2)Toulouse Lyon Brussels

Study coordinator Pr C Le Tourneau (Institut Curie)

DSMB

OBJECTIVES To determine dose-limiting toxicities (DLTs) and the maximum tolerated dose (MTD)

To evaluate the pharmacokineticspharmacodynamics (PKPD) effects of AsiDNAtrade based on biomarkers of activity in blood and in tumor tissues

APRIL 2018FIRST PATIENT DOSED

TREATMENT SCHEDULE

Dose Level 1

200 mg

Dose Level 6

1800 mg

3 patients

Dose Level 2

400 mg

4 patients

Dose Level 3

600 mg

3 patients

MAY 2019 END OF STUDY

1-hour IV infusion

DAY 1 21 2 3 8 15

CYCLE 1CYCLE 2 and beyond once a week

DRIIV-1 study evaluating AsiDNAtrade via IV administration all safety and activity endpoints metDNA Repair Inhibitor administered IntraVenously in patients with advanced solid tumors having failed previous anticancer therapies

Dose Level 4

900 mg

6 patients1 DLT

ACTIVE DOSES - THERAPEUTIC WINDOW

NOVEMBER 2018 BIOACTIVITY

Activity as early as dose level 2 MTD not reached at dose level 5

November 2019

Dose Level 5

1300 mg

6 patients1 DLT

SELECTED AS OPTIMAL DOSE FOR DRIIV-1b IN COMBO w CHEMO

Not administered sufficient therapeutic window

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

20DRIIV-1 study Safety Overview - DL1 to DL5n = 22 patients ndash 153 infusions

November 2019

AsiDNATM 200mg (DL1) 400mg (DL2) 600mg (DL3)

No drug-related serious adverse events

No dose-limiting toxicity

No cumulative relevant safety

Only grade 1 amp 2 drug-related adverse events

AsiDNATM 900mg (DL4) 2 related SAEs

Orthostatic hypotension grade 3 (unlikely related)

Hepatic enzyme increased grade 4 (possibly related) =gt 3 additional patients (DLT)

AsiDNATM 1300mg (DL5) 1 related SAEs

Hepatic enzyme increased grade 3 (unlikely related) =gt 3 additional patients (DLT)

Maximum tolerated dose (MTD) was not reachedFavorable safety profile at active doses providing a comfortable therapeutic window

Source Onxeo data on file

181 (89)

22 (11)1

204 adverse events

Grade 12 Grade 3 Grade 4

related 5

related 23

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

21DRIIV-1 study ndash Activity (PD) - Proof-of-Mechanism in man

Significant increase of activity biomarkers as early as DL2 (400 mg)Activity biomarkers increase gH2AX and pHSP90

Tumor proliferation biomarker decrease Ki67

Consistent activity in all patients tested from DL2 (400mg) to DL4 (900mg) supporting AsiDNAtrade target engagement via IV route

At DL3 (600mg) 2 patients w relapsed multi-treated mCRC controlled without

progression at the end of 2nd treatment cycle amp treatment maintained for 3 months

AsiDNAtrade robust target engagement via IV route is confirmed

DL3 (600 mg) selected as optimal dose for further combination studiesActivity

November 2019 Metastatic colorectal cancer - 21- day treatment cyclesSource Onxeo data on file

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

22DRIIV-1b study in combination with carboplatin with or without paclitaxelin patients with advanced metastatic solid tumors (eligible to the selected chemotherapy regimen)

November 2019

Positive intermediate results from Part 1 of the studyPart 2 started with first results expected by year end 2019

PHASE 1b

Extension of DRIIV-1 mono study

Open-label 3+3 patient cohort

Up to 15 patients

2 centers in Belgium

DSMB

OBJECTIVES To confirm AsiDNAtrade IV at 600 mg safety and tolerance in combination

To detect signal of efficacy (RECIST criteria)

To explore predictive biomarker (gene signature retrospective analysis on initial biopsy)

TREATMENT SCHEDULEASIDNATM 1-hour IV infusion

AsiDNAtrade

DAY 1 22 2 3 8 15

CYCLE 1

Q3 2019PART 1 INTERMEDIATE RESULTS

29

Carbo 3 w CarboPacli w PacliPacli Pacli

AsiDNAtrade AsiDNAtrade AsiDNAtrade AsiDNAtrade

END Q4 2019PRELIMINARY EFFICACY OUTCOMES

AsiDNAtrade 600 mg

Part 1 carboplatin

AsiDNAtrade 600 mg

carboplatin + paclitaxel

AsiDNAtrade 400 mg

carboplatin + paclitaxel

Part 2(ongoing)

+

+

+

6 pts

6 ptsPart 3

3 patients whose metastatic tumors were progressing at inclusionStable disease (no tumor progression) in 23 pts still being treatedSatisfactory tolerance of the combination

3 pts

CYCLE 2 and beyond once a week

If necessary (DLT)

MAY 2019FIRST PATIENT DOSED

H1 2020 END OF STUDY

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

23AsiDNAtrade IV Current Clinical Program Solid tumors with high unmet medical needs

November 2019

Synergy

Phase 1b StudyEfficacySafety of the combo AsiDNAtrade with carboplatin +

paclitaxel

bull Advanced metastatic solid tumors eligible to carboplatin with or without paclitaxel (TNBC Ovarian cancers Lung Head amp Neckhellip)

bull Objectives confirm AsiDNAtrade readiness for phase 2 in combo (safety profile and efficacy signal detection)

FPI May 2019 ndash positive results from part 1 with carboplatinFirst results from part 2 (carboplatin + paclitaxel) expected late Q4 2019Next step Phase IIa to start in 2020

Resistance

Phase 1b2 StudyAbrogation of PARPi

resistanceAsiDNAtrade in combo with PARP inhibitor

bull Ovarian Breast cancer bull Objectives confirm AsiDNAtrade potential to abrogate tumor resistance to PARPi andor

synergistic effects

FPI expected H1 2020

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

FINANCIALS amp OUTLOOK

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

25

Financiegravere de la Montagne16

Other institutions19

Retail60

Misc 5

Financials and share structure

Cash position of euro63m at 06302019

New equity line set up in November 2019 provides cash runway to Q3 2020

Shares outstandingFully diluted

57m596m

Dual listing Euronext Paris amp Nasdaq Copenhagen

ISIN FR0010095596

at 083119 at 013119

November 2019

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

26

AsiDNAtrade OX401

Today

On-going preclinical work on new combinations

Preliminary Results of DRIIV 1b

Filing of Phase 1b2 combo study w PARPi

New compound from platONtrade entersregulatory preclinical evaluation and CMC In-vitro validation

H1 2020

H2 2020

DRIIV 1b full data set

Niraparib combo study ( ovarian cancer) preliminary data In-vivo proof-of-concept

Niraparib combo study additional data

Multiple near to mid-term value-creating RampD milestones

November 2019

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

APPENDICES

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

28AsiDNAtrade Publications (12)

Hyperactivation of DNA-PK by double-strand break mimicking molecules disorganizes DNA damage response Quanz M et al PLoS One 2009 4e6298

Histone γH2AX and Poly(ADP-Ribose) as Clinical Pharmacodynamic Biomarkers Redon CE et al Clin Cancer Res 2010 16(18)

Comparison of distribution and activity of nanoparticles with short interfering DNA (Dbait) in various living systems Berthault N et al Cancer Gene Ther 2011 18695-706

Heat shock protein 90 (Hsp90) is phosphorylated in response to DNA damage and accumulates in repair foci Quanz M et al J Biol Chem 2012 2878803-15

Preclinical study of the DNA repair inhibitor Dbait in combination with chemotherapy in colorectal cancer Devun F et al J Gastroenterol 2012 47266-75

Pharmacokinetics and toxicity in rats and monkeys of coDbait a therapeutic double-stranded DNA oligonucleotide conjugated to cholesterol Schlegel A et al Mol Ther Nucleic Acids 2012 1e33

Distribution and radiosensitizing effect of cholesterol-coupled Dbait molecule in rat model of 5 glioblastoma Coquery N et al PLoS One 20127(7)e40567

Resistance to PARP-Inhibitors in Cancer Therapy Montoni A et al Front Pharmacol 2013 4 18

Kinesin KIFC1 actively transports bare double-stranded DNA Farina F et al Nucleic Acids Res 2013 414926-37

Inhibition of DNA damage repair by artificial activation of PARP with siDNA Croset A et al Nucleic Acids Res 2013 417344-55

DNA-PK target identification reveals novel links between DNA repair signaling and cytoskeletal regulation Kotula E et al PLoS One 2013 8(11)e80313

Colorectal cancer metastasis the DNA repair inhibitor Dbait increases sensitivity to hyperthermia and improves efficacy of radiofrequency ablation Devun F et al Radiology 2014 270736-46

A preclinical study combining the DNA repair inhibitor Dbait with radiotherapy for the treatment of melanoma Biau J et al Neoplasia 2014 16835-44

An update on PARP inhibitors for the treatment of cancer Benefif S et al

Dbait An innovative concept to inhibit DNA repair and treat cancer Biau J et al Bull Cancer 2016 103 227ndash235

The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis Herath NI et al Mol Cancer Ther 2016 Jan15(1)15-22

Targeting DNA Repair in Cancer Beyond PARP Inhibitors Brown JS et al Cancer Discov December 21 2016 DOI 1011582159-8290CD-16-0860

Targeting DNA repair by coDbait enhances melanoma targeted radionuclide therapy Viallard C et al Oncotarget 2016 Mar 157(11) 12927-36

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients in with skin metastases from melanoma Le Tourneau C et al Br J Cancer 2016 May 24114(11)1199-205

Potentiation of Doxurubicin efficacy in hepatocellular carcinoma by the DNA repair inhibitor DT01 in preclinical models Herath NI et al Eur Radiol 2017 Oct 27(10)4435-4444

Drug Driven Synthetic Lethality bypassing tumor cell genetics with a combination of AsiDNA and PARP inhibitors Jdey W et al Clin Cancer Res 2017 Feb 1523(4)1001-1011

29AsiDNAtrade Publications (22)

Micronuclei Frequency in Tumors Is a Predictive Biomarker for Genetic Instability and Sensitivity to the DNA Repair Inhibitor AsiDNA Jdey W et al Cancer Res 2017 Aug 1577(16)4207-4216

The DNA Repair Inhibitor Dbait Is Specific for Malignant Hematologic Cells in Blood Thierry S et al Mol Cancer Ther 2017 Dec16(12)2817ndash27

Combining the DNA Repair Inhibitor Dbait With Radiotherapy for the Treatment of High Grade Glioma Efficacy and Protein Biomarkers of Resistance in Preclinical Models Biau J et al Front Oncol 2019 Jun 199549

Moving From Poly (ADP-Ribose) Polymerase Inhibition to Targeting DNA Repair and DNA Damage Response in Cancer Therapy Gourley C et al J Clin Oncol 2019 May 3

AsiDNAtrade treatment induces cumulative antitumor efficacy with a low probability of acquired resistance Jdey W et al Neoplasia (2019)21 863ndash871

Posters AACR 2013

Preclinical study of Dbait an inhibitor of three DNA repair pathways in breast cancer treatment

ASCO 2015

First-in-human phase I study of the DNA repair inhibitor DT01 in combination with radiotherapy in patients with skin metastases from melanoma

AACR 2017

AsiDNAtrade induces tumor sensitivity to PARP inhibitors in homologous recombination proficient breast cancer

AACR 2018

AsiDNAtrade and HDAC inhibitors A cross-potentiation team work to kill tumor cellsEvolution of tumor cells under Dbait (AsiDNA) treatment results in ldquoautosensitizationrdquo

AACR 2019

Molecular analysis of the mechanism of action of AsiDNAtrade brings new clues on DNA damage response regulationAsiDNAtrade a novel DNA repair inhibitor to radio-sensitize aggressive medulloblastoma subtypesAsiDNAtrade abrogates acquired resistance to PARP inhibitorsDevelopment of a Biomarker-driven patient selection strategy for AsiDNAtrade treatment

CONTACTSJudith Greciet ndash CEO

Nicolas Fellmann ndash CFOTel +33 1 45 58 76 00 contactonxeocom

COMPANY INFORMATIONwwwonxeocom