harnessing the therapeutic power of plants andrew gallagher programme manager 1 plants as providers...
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Harnessing the Therapeutic Power of Plants
Andrew GallagherProgramme Manager
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Plants as Providers of Fine Chemicals Conference2012
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Introduction
An innovative life science company based near
Oxford with research facilities in China that uses its
plant chemistry platform to develop patented and
well-characterised botanical actives for use in
pharmaceuticals, nutraceuticals, and personal care
products
Who is Phynova?
Plants as a Source of Medicines
• Plants contain a wide array of secondary metabolites with inherent biological activity
• As plants can’t evade or fight back against predators, they rely on these chemical defences to fend off animal and micro-organism attack
• The ability to synthesize secondary metabolites has been selected throughout course of evolution and address specific needs of the plant, e.g.:
– Volatile scents to attract pollinators to enhance fertilization rates
– Toxic chemicals to ward off pathogens and herbivorous browsers
– Compounds to suppress the growth on neighbouring plants
• This diversity of chemical compounds makes plants a valuable source of new medicinal compounds
3Schmidt et al. (2007). Revisiting the ancient concept of botanical therapeutics. Nature Chemical Biology; 3 (7): 360-366
Plants as a Source of Medicines - Continued
• A large proportion of small-molecule drugs today are either:
– Natural products– Derived from natural products (semi-synthetically), or – Have a natural product inspired pharmacophore
• Abundance of natural product-based drugs begs the question of whether plant secondary metabolites & their derivatives perform better than randomly synthesized compounds?
• Plant metabolites, enzymes, receptors, and regulatory proteins have common evolutionary roots and they co-evolved to interact with one another
– Structures and functions may have diverged over time but, on average, natural products make better ligands for human clinical targets than randomly synthesized compounds
4Schmidt et al. (2007). Revisiting the ancient concept of botanical therapeutics. Nature Chemical Biology; 3 (7): 360-366
Magic Shotgun vs Magic Bullet
• Modern drug discovery has traditionally had a magic bullet approach, i.e. one molecule, one receptor
• More and more often this approach is seen as inadequate and diseases are being treated with a combination of many single-component drugs
– Combination therapies are particularly suited for complex chronic diseases such as cancer, diabetes, infectious diseases
• Plants have always relied on mixtures of biologically active molecules to defend themselves from diseases and predation
• Plant extracts can act as a combination therapy in a single composition, i.e. one extract, multiple targets
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Phynova embraces the magic shotgun ethos and all its products are purified plant extracts
Phynova’s Development Platform
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10 000 plants used in Chinese medicine
Discovery Engine (China)
Cost effective
Human use reduces risk
Development Path(UK)
•Demand driven•High value markets
•Unmet needs
Pharma products
Patents&
Regs (UK)
Functional ingredient
sTHMPs
Phynova utilises the rich history of TCM as a discovery engine to identify and develop patented medicinal products for global healthcare markets
Pharma Case Study - Melokinex™
Identified major unmet therapeutic
need with $1 billion + market
Data mining and creative
candidate selection
(~30 plants)
Successfully completed Phase 2b
clinical study
Preclinical evaluation;
IP generation
Activity-guided
fractionation and lead candidate selection
The development model utilised by Phynova streamlines the R&D process so that drug candidates in high value, low competition markets are rapidly identified and advanced to proof-of-concept
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Introduction: Postoperative Ileus
• Postoperative ileus (POI) is a temporary dysmotility of the GI tract following surgery
• POI is accepted as an inevitable complication of major surgery
• Although rarely life-threatening it is associated with:
Considerable patient discomfort
Increased hospitalisation
Increased hospital resource utilisation
• Incidence of POI following abdominal surgery is 6.3% - 10.7%, but some studies report incidence of up to 20%1
1. Wittbrodt E. The impact of postoperative ileus and emerging therapies. Pharmacy and Therapeutics, 2006; 31(1): 39-59.
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Economic Burden Associated with POI
(Taken from: Wittbrodt E. The impact of postoperative ileus and emerging therapies. Pharmacy and Therapeutics, 2006; 31(1): 39-59).
+ 4 days hospitalisatio
n + $6k
hospital costs
Based on conservative estimates of POI incidence (6%) and the annual number of abdominal surgeries in the USA (~12m) the increased financial burden to US healthcare is $5 billion annually
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Multiple Factors Contribute to POI
Endogenous opiate release
Inflammation
Autonomic nervous system
Enteric nervous system
Hormones and neuropeptides
Anaesthesia
Exogenous opiates for pain relief
Surgical trauma
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Current Treatments Approaches for POI
• Only one approved pharmaceutical treatment for POI – alvimopan (Entereg®), a peripherally acting μ-opioid receptor antagonist
• Treatments in development include – ghrelin receptor agonists,
– 5HT4 receptor antagonists
– opioid receptor antagonists
• Other treatment options include– use of nasogatric tubes,
– early postoperative ambulation and feeding,
– epidural analgesia,
– Rescue medication such as laxatives, and anti-inflammatories
Even though there are treatment options available, benefit is often marginal
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MelokinexTM: Data Overview
• In vivo studies show that Melokinex™ improves mechanically-induced and drug-induced bowel immotility in mice and rats
• Promotes motility in normal mice
• Long history of safe human usage of the constituent plant – used traditionally as an emetic
• Clean acute toxicology in mice (LD50 not detectable)
• MTD is 229x clinical dose
• Causes no skin irritation or sensitization (allergic reaction)
• Clinical data shows it significantly alleviates POI
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.6 m
g/k
g
99
.2 m
g/k
g
19
8.4
mg
/kg
Pseudo-surgery
Mechanical Injury
Neostigmine Control
Melokinex
2030405060708090
100
Imp
ell
ing
pe
rce
nta
ge
(%
)
Promotion of GI Motility in Normal & Hypofunction Animals
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A single administration of Melokinex™ significantly (**p<0.01; *p<0.05) shortened excretion intervals and increased the quantity of the faeces in normal, and chemically & surgically induced hypofunction mice
49.6 mg/kg 99.2 mg/kg 198.4 mg/kgNormal control Neostigmine
(0.15mg/kg)Melokinex
020406080
100120140160
Tim
e t
o f
irs
t e
xc
reti
on
(m
in)
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.6 m
g/k
g
99
.2 m
g/k
g
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8.4
mg
/kg
Normal Control
Atropine Treated
Neostig-mine Con-
trol
Melokinex
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Tim
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irs
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Atropine & surgery induced hypofunctionNormal mice
49.6 mg/kg 99.2 mg/kg 198.4 mg/kgNormal control Neostigmine
(0.15mg/kg)Melokinex
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an
tity
of
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******
49.6 mg/kg 99.2 mg/kg 198.4 mg/kgNormal group
Atropine Treated
Neostigmine Control
Melokinex
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Imp
ell
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pe
rce
nta
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Effective Agent Throughout the GI Tract
Melokinex™ was shown to be effective in increasing enterokinesia in both the small and large
intestine
Intestine enterokinesia in the small intestine (n=10)
49.6 mg/kg 99.2 mg/kg 198.4 mg/kgNormal control Neostigmine
GroupMelokinex
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40
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60
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Imp
elli
ng
per
cen
tag
e (%
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30.5 mg/kg 61 mg/kg 122 mg/kgNormal control Neostigmine
ControlMelokinex
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Imp
elli
ng
pe
rce
nta
ge
(%
)
Intestine enterokinesia in the large intestine (n=10)
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******
**
** P<0.01
** P<0.01
Effects Colon Enterokinesis
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(0~
30m
in)
0~
30m
in
30~
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in
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90m
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120m
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After Medication
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After Medication
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The contraction waves and amplitude indices significantly increased within 30 minutes after a rectal administration of Melokinex in anaesthetised rats (peak between 30-60 minutes)
Proximal colon constriction in anaesthetised rats (n=5)Negative control Positive control
(neostigmine)Melokinex 5mg/kg Melokinex 10mg/kg
Notes: Compared with self, before medication: # P<0.05, ##P<0.01Compared with negative control: * P<0.05, ** P<0.01
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Phase II Safety & Efficacy Study Design
Objective Investigate the efficacy and safety of Melokinex
Design
End points
Primary: First flatus/stool after surgerySecondary: First bowel sound
SampleSize
Active dose 72 patients Placebo 72 patients
Randomised, double blind, placebo controlled, multicentre
Efficacy Analysis – Primary Endpoints
First passing flatus after surgery
– Data evaluated using Kaplan-Meier survival curve
– Median time to first passing flatus after surgery was 87hrs hours on placebo and 58 hours on active (P<0.0001)
– Lower and upper quartiles (25%, 75%) were 65 hours and 94 hours for placebo
– Lower and upper quartiles (25%, 75%) were 42 hours and 76 hours for active
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Kaplan-Meier Survival Curve: 1st Flatus (FAS)
Rate
(%
)Hours post-surgery
ActivePlacebo
P < 0.0001
Patients receiving Melokinex on average experienced first flatus 29 hours earlier than those who
received the placebo
Efficacy Analysis – Primary Endpoints
First passage of stool after surgery
– Median time to first bowel movement after surgery was 111 hours on placebo and 77 hours on active (P<0.0001)
– Lower and upper quartiles (25%, 75%) were 88 hours and 128 hours for placebo
– Lower and upper quartiles (25%, 75%) were 43 hours and 92 hours for active
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Patients receiving Melokinex on average had a 1st bowel movement
34 hours earlier than those who
received the placebo
Hours post-surgeryR
ate
(%
)
Kaplan-Meier Survival Curve: 1st Bowel Movement (FAS)Active
Placebo
P < 0.0001
Weak Affinity for Typical GI Motility Targets
Melokinex has shown a limited (significant response >±50%) in a series of GI-related enzyme and radioligand binding assays
Data does not however support the strong pharmacological effect seen and suggests that the promoting of GI motility might be contributed by a multivalent mechanism of action
Functional Ingredients Case Study - IminoNorm™ & PhynoRadiance™
Research began for anti-diabetic drug
candidate
Activity assays suggested cosmetic
applications in addition to diabetes
From one plant have pharma,
nutraceutical and
cosmeceutical products
Collaboration with global soft drinks company for use of IminoNorm for
soft drinks industry in China
PhynoRadiance now marketed as
cosmetic ingredient for skin lightening
The multiple secondary metabolites not only make plants excellent therapies for complex, multivalent diseases, but also allows them to be used for different conditions
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The Convergence of Food and Pharma
• Global shift from reactive treatment of health disorders through the use of drugs, to proactive, preventative approach by consumers
• Two big trends are shaping the health and wellness markets:
– Natural movement that centres on a healthy balanced diet– Nutraceutical movement that focuses on adding beneficial active
ingredients to achieve specific health functions
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IminoNorm™ - Solution for ‘Diabesity’
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● IminoNorm is a functional ingredient that significantly reduces blood glucose levels and improves the glycaemic index of carbohydrate rich goods
● IminoNorm acts on multiple biochemical pathways including
Inhibiting carbohydrate digestion
Output of glucose from glycogen stores
IminoNorm™ In vivo Activity
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0 30 60 90 120 1502.00
2.50
3.00
3.50
Impact on postprandial blood glucose levels in rats (n=10)
Placebo
ig 25mg/kg
ig 50mg/kg
ip 15mg/kg
ip 30mg/kg
ig 25mg/kg miglitol
Time after starch administration (minutes)
Pla
sm
a g
lucose (
mm
ol/L)
• IminoNorm™ was shown to potently reduce post-prandial blood glucose levels in vivo
• ig 50mg/kg test sample is as effective as miglitol (Glyset®) at lowering blood glucose levels
• Interestingly, the ip route also reduced blood glucose levels, supporting the multiple mechanism of actions suggested by enzyme
studies
Human Glucose Tolerance Study
• Co-ingestion with 50g soft sugar resulted in a reduction of the AUC 2hr and AUC 3hr by 53.5% and 50.8% respectively
compared with placebo
• Activity comparable with the control, 50mg miglitol
• The strong efficacy supports the magic shotgun approach as lower levels of synergistically acting compounds work together
to produce a potent result
Placebo BCME Miglitol0.00
10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00
100.00 110.00
Glucose Absorbtion_ZZ
AUC2hAUC3h
AUC
(% o
f con
trol
)
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Other Roles of α-Glucosidase in the Body
Cu2+ Cu2+
α-glucosidase I α-glucosidase II α-glucosidase II
Folding
Copper incorporation
CNX/CRT
Glucosidase plays a key role in the glycan processing and maturation of the enzyme tyrosinase • The glycan is sequentially trimmed by α-glucosidase I and II allowing the
attachment of molecular chaperones calnexin (CNX) and calreticulin (CRT) through their recognition on monoglucosylated N-glycans of tyrosinase
• Tyrosinase is folded by the chaperones resulting in active tyrosinase
• α-Glucosidase inhibitors prevent the necessary oligosaccharide trimming required for chaperone attachment and folding.
Symbols: blue square = N-acetyl glucosamine, blue circle = mannose, green triangle = glucose25
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Role of Tyrosinase in Melanin Synthesis
Tyrosinase, the rate-limiting enzyme in the biosynthesis of melanin, is an ideal therapeutic target in combating hyperpigmentation.
HO
COOH
NH2 HO
COOH
NH2
HO
O
COOH
NH2
O
HO N
O
COOH HO NH
HO
O NH
O
Tyrosinase Tyrosinase
Tyrosine Dopa Dopaquinone
Dopachrome 5,6-Dihydroxyindole Indole-5,6-quinone
MelaninTyrosinase
Reduction of the activity of tyrosinase has dramatic consequences on pigmentation.
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PhynoRadiance™ - A Novel Ingredient for Skin Whitening
• Produced from same plant as IminoNorm
• Inhibits melanin formation through a novel mechanism of action
• Reduces skin hyperpigmentation
• Clinical proven safe and efficacious
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PhynoRadiance™ - Clinical Results
• The study reported that the formulation induced a significant lightening effect after 28-days of twice-daily usage
• There was a significant increase in skin lightness (L* parameter)
• There was a significant decrease in skin pigmentation (ITA parameter)
• 86% of subjects reported they perceived their skin to be more uniform in colour
• 81% of subjects reported that they found their skin clearer
• 86% of subjects would continue to use the product and 96% would purchase it
Day 0Day 28
59.4
59.6
59.8
60
60.2
60.4
60.6
60.8
0.20%
0.50%
Effect of PhynoRadiance on L*
0.20%0.50%
Day 0Day 28
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27.5
28
28.5
29
29.5
30
0.20%
0.50%
Effect of PhynoRadiance on ITA
0.20%0.50%
Advantages & Challenges of Botanical Drugs
• Botanical drugs offer many advantages over NCEs:
– Historical use reduces product failure rate – Lower concentrations of multiple active reduces toxic burden
• Botanical drugs are however a highly specialised field with unique challenges
• High cost of screening and difficulty in isolation and characterisation of active fractions
– Prior knowledge of the plants reduces this cost
• Product quality and batch-to-batch consistency are essential in order to satisfy both regulatory and consumer demands
– Standardisation only possible when bulk of bioactive components is known and their range of levels has been established
• Products have to be produced to pharmaceutical GMP
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Strict Process Control from Plant Raw Material to Finished Product
• Plant growing site selection
• Application of GAP guidance
• QC on raw materials including authenticity of the plant species, microscopic identification, impurity tests and assay for chemical markers
• Contamination tests including heavy metals, pesticides and aflatoxins
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Strict Process Control from Plant Raw Material to Finished Product
• GMP manufacturing of the plant extracts and the finished product
• Batch-to batch consistency ensured through use of:
– Qualitative and quantitative fingerprinting of marker compounds e.g. HPLC, GC-MS, HPTLC
– Bioassays to ensure biological activity (marker compound may not be the active component)
• EU pharmacopoeial contaminant levels
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Regulatory Support for Botanical Drugs
• Botanical drugs represent the third paradigm in drug development
• Detailed guidelines on toxicology requirements if previous human use
• Shorter development times and reduced development costs
• Regulatory parity with synthetics & biologicals
Global Interest in TCM
• Asian medicine has been receiving a lot of attention recently:– Dec 2011 Nature Outlook supplement on Asian medicine
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New GSK R&D Unit Focusing on TCM
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Contact Details
Andrew Gallagher
Programme Manager
Email: [email protected]
Tel: +44(0) 1993 880 700
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PHYNOVA GROUP LTDPHYNOVA HOUSE, 16 BLENHEIM OFFICE PARK,
LONG HANBOROUGH, OXON OX29 8LN, UK
www.phynova.com