NKTR-214, an engineered cytokine, synergizes and improves efficacy of anti-cancer vaccination in the treatment of established murine melanoma tumor
Meenu Sharma1, Faisal Fa’ak1, Louise Janssen1, Hiep Khong1,2, Zhilan Xiao1, Yared Hailemichael1, Manisha Singh1, Christina Vianden1, Adi Diab1, Jonathan Zalevsky3, Ute Hoch3, Willem W. Overwijk1,2 1Department of Melanoma Medical Oncology, University of Texas MD Anderson Cancer Center, Houston, TX 77030
2University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX 77030 3Nektar Therapeutics, 455 Mission, Bay Blvd South, San Francisco, CA 94158
Pmel-1 CD8+ T cells CD25+ Foxp3+ Tregs Pmel-1/Tregs Ratio
• NKTR-214 efficiently synergized with vaccination, potently suppressing tumor growth and improving
survival of mice compared to vaccination with IL-2.
• NKTR-214 significantly enhanced pmel-1 CD8+ T cell numbers in tumor and spleen.
• NKTR-214 specifically decreased numbers of immune-suppressive Tregs in the tumor while maintaining
their numbers in spleen.
• Despite the induction of very strong CD8+ T cell responses and anti-tumor activity, no gross toxicity was
observed.
• Accumulating evidence suggests that low baseline tumor infiltrating lymphocytes (TILs) are predictive for poor response to checkpoint inhibitor immunotherapies,1,2 thus agents designed to specifically activate and expand TILs may improve the overall success and utility of checkpoint inhibitor therapies in patients with low TILs
• Interleukin-2 (IL-2) is a cytokine that activates and expands tumor killing lymphocytes, but also potently activates suppressive T regulatory cells (Tregs) by binding to the heterotrimeric IL-2Rαβγ
• NKTR-214 is a CD122-biased cytokine agonist conjugated with multiple releasable chains of polyethylene glycol and designed to provide sustained signaling through the heterodimeric IL-2 receptor pathway (IL-2Rβγ) to preferentially activate and expand effector CD8+ T and NK cells over Tregs3
In this pre-clinical study, we investigated whether NKTR-214
can promote expansion and function of vaccination-induced,
tumor specific effector CD8+ T cells using the murine B16
melanoma model. We also studied how NKTR-214 impacts
the localization of effector CD8+ T cells and Tregs to tumor
and spleen.
1. No treatment 2. Aldesleukin (100,000 IU X 5 doses - D0,D1,D2)_every 8 days 3. NKTR-214 (0.2 mg/kg) _every 8 days 4. Vaccine 5. Vaccine + aldesleukin (100,000 IU X 5 doses D0,D1,D2)_every 8 days 6. Vaccine+ NKTR-214 (0.2 mg/kg)_every 8 days
Mice: C57BL/6
D0
Gp100 peptide TLR-7 agonist Anti- CD40 IL-2 or NKTR-214
D1
IL-2
D2
IL-2 NKTR-214 Or IL-2
D8
NKTR-214 Or IL-2
D16
D-6
Tumor Induction 300,000 B16 wild type cells
NKTR-214 Or IL-2
D24
Treatment repeated till
experimental end point
o Gp100 peptide (50 ug/mouse)-L-tyr (adjuvant) o anti –CD40 (50 ug/mouse) o TLR-7 agonist (Imiquimod- 5 mice/pack)
Vaccine formulation
0 20 40 60 80 1000
20
40
60
80
100
No#treatmentNKTR-214#Aldesleukin
Vaccine##+#AldesleukinVaccine#+#NKTR-214#
Vaccine
**p= 0.0031
Days#a=er#vaccina?on
Perc
ent s
urvi
val
Pmel-1 T cell response Tregs
Survival
0 20 40 60 800
50
100
150
Untreated
NKTR321444Aldesleukin4
4Vaccine4Vaccine4+4Aldesleukin
p=0.039Vaccine4+4NKTR32144*
p=0.018*
Days4a@er4vaccinaBon
Tumor4size4(m
m² )
0"
50"
100"
150"
0" 10" 20" 30" 40" 50" 60" 70" 80"
No"treatment"
0"
50"
100"
150"
0" 10" 20" 30" 40" 50" 60" 70" 80"
Vaccine"!
Days"a9er"vaccina;on"
0"
50"
100"
150"
0" 10" 20" 30" 40" 50" 60" 70" 80"
NKTR?214"
0"
50"
100"
150"
0" 10" 20" 30" 40" 50" 60" 70" 80"
Aldesleukin"
0"
50"
100"
150"
0" 10" 20" 30" 40" 50" 60" 70" 80"
Vaccine""+""
Aldesleukin"
0"
50"
100"
150"
0" 10" 20" 30" 40" 50" 60" 70" 80"
Vaccine""+"
"NKTR?214"Tumor"size"(mm
2 )"
Tumor size
0
20
40
60
80
100
No#treatment
Vaccine#+#Aldesleukin
Vaccine#+#NKTR7214
Vaccine
45±8.8&%& 12±5.2&%& 6±3.3&%& 1.2±0.8&%&
No&treatment& Vaccine& Vaccine&&+&
Aldesleukin&
Vaccine&&+&
NKTRB214&
Foxp
3&
CD4&
Introduction
Objectives
NKTR-214 improves anti-tumor efficacy of peptide vaccines
NKTR-214 impacts the localization of Pmel-1 cells and Tregs between tumor and spleen
Tumor Spleen
Conclusions
References
Pmel-1 CD8+ T cells CD25+ Foxp3+ Tregs Pmel-1/Tregs Ratio
Pmel%1/Treg+ra-o
+(tum
or)+
0
1000
2000
3000
4000 **
0
200000
400000
600000
****
**
**
Numbe
r'of'P
mel,1'CD8
+'T'cells/'g
ram'of'tum
or'
10.5±2.3%) 11.4±1.2)%) 12.2±3.3)%) 11±2.4)%)
No)treatment) Vaccine) Vaccine))+)
Aldesleukin)
Vaccine))+)
NKTR@214)
Foxp
3)
CD4)
0
500000
1000000
1500000
2000000
***
No#treatment
Vaccine#+#Aldesleukin
Vaccine#+#NKTR7214
Vaccine
Num
ber'o
f'Pmel,1/'Spleen
'
0
20000
40000
60000
80000
100000
*ns
Num
ber'o
f'Tregs'/'Spleen'
0
50
100
150
***
Pmel%1/Treg+ra-o
+(Spleen)+
Tregs (% of CD4+ T cells)
Pmel-1 (% of CD8+ T cells)
3.4±2.2%' 72.3±5.2'%' 91.1±3.5'%' 95.2±3.5'%'
No'treatment' Vaccine' Vaccine''+'
Aldesleukin'
Vaccine''+'
NKTRA214'
Thy1.1
'
CD8'
Thy1.1
&
0.1±0.8%& 34.3±4.2&%& 65.8±3.5&%& 75.2±3.5&%&
No&treatment& Vaccine& Vaccine&&+&
Aldesleukin&
Vaccine&&+&
NKTRE214&
CD8&
transfer of TCR transgenic pmel-1 CD8+ T cells
D0#
Gp100#pep(de#TLR-7#agonist#An(-#CD40#Pmel-1#NKTR-214#
T#cell#response#:#Tumor/spleen#
D-6#
Tumor#Induc(on##300,000#B16#wild#type#cells#
D7#
1) Daud AI, Wolchok JD, Robert C, et al. J Clin Oncol. [Epub ahead of print] DOI:10.1200/JCO.2016.67.2477 2) Daud AI, Loo K, Pauli ML, et al. J Clin Invest. 2016;126(9):3447-52 3) Charych DH, Hoch U, Langowski JL, et al. Clin Cancer Res. 2016;22(3):680-90. 0 10 20 30 40 50 60 70
0
20
40
60
80
100Untreated
NKTR,21400Aldesleukin0
0Vaccine0Vaccine0+0AldesleukinVaccine0+0NKTR,2140 ***
***< 0.0001
< 0.0001
Days.a/er.vaccina6on
Thy1
.1 +
Pm
el-1
T c
ells
(% o
f CD
8+ T
cel
ls)
0 10 20 30 40 50 60 700
20
40
60
80
100Untreated
NKTR,21400Aldesleukin0
0Vaccine0Vaccine0+0AldesleukinVaccine0+0NKTR,2140 *
*p=0.03
p=0.01
Days.a/er.vaccina6on
CD
25+
Foxp
3+ T
regs
(% o
f CD
4+ T
cel
ls)
0
1000
2000
3000
4000
*
*ns
**
*Num
ber'o
f'Tregs/'gram
'of'tum
or'
