The document discusses various animal models used to screen drug candidates for therapeutic efficacy prior to human trials. It summarizes several key animal models: [1] Anti-infective models evaluate a drug's ability to relieve infection in animals; [2] Anti-cancer xenograft models test drugs' effects on tumor size and growth in mice; [3] Anti-inflammatory models assess a drug's impact on reducing inflammatory responses in mice. The models are useful but limited precursors to human studies due to interspecies differences in anatomy, physiology and metabolism.

1. Biology Services
Randy Jones, D.V.M., Ph.D.
Diplomate A.B.V.T. & A.B.T.
Vice President Biology Services
Ricerca Biosciences, LLC
May 23, 2007

2. Introduction
• Animal models screen drug candidates for potential
therapeutic efficacy
• Confounded by species of animal, metabolism,
pharmacokinetics, organ system anatomy, and physiology
• An initial opportunity to integrate biology and chemistry
• Anti-infective, oncology screening, and anti-inflammation
models are likely to remain important for development of
drug candidates for an aging population
• Established disease models require less time and
development expense but may lack specificity
• Brief application of anti-infectivity models, in vivo anti-tumor
assays, and anti-inflammatory models will be presented

3. Biotech Business Model
Is the Bio-Entrepreneur more successful
than Pharma at drug development?
• Typical biotech customer proceeds cautiously with one or two
projects and moves to combinations of biology and chemistry
• Need to develop their “one-and-only” lead into an IND
• Cash Flow – “do or die”
• Smaller organizations – fewer layers

4. Overview
Animal models of human disease are used to screen
drug candidates for potential therapeutic efficacy
focusing on pharmacology and mechanism of action
• Ethical considerations support the judicious use of animals
prior to first-in-human use
• Drugs are not used to treat normal people
• Drug candidates are tested for toxicity on physiologically normal,
juvenile animals (rodent & non-rodent)
• Pharmacology vs toxicology endpoints
• Mechanism of action – homology, specificity….

5. Overview (Continued)
The predictive nature of the model and its potential to
extrapolate to a human disease is impacted by:
• Species of animal
• Metabolism – constitutive and inducible capacity
• Pharmacokinetics – drug-ability
• Organ system anatomy
• Physiology

6. Metabolite Profile
%Loss of Parent Compound
120
Risk Management
100
% Loss of Parent
80
60
Cyn vs Rh
!
40
20
Teenage athlete vs
!
0
0 5 10 15 20 25 30 35
Geriatric poly-pharmacy
Incubation Time (min.)
Dog Cyn Monkey Rh Monkey Human Mouse Rat
Therapeutic index
!
%Increase in Metabolite Formation
Clinical Indication
!
% Increase in Metabolite
60
Bimodal or uniform
!
50
pharmacogenomics
40
30
FDA/ICH guidelines
20
!
10
0
0 5 10 15 20 25 30 35
Time (min.)
Dog Cyn Monkey Rh Monkey Human Mouse Rat

7. Pharmacokinetics
Rapid In Vivo screening Parent (Pro-drug)
700
Pharmacokinetic Parameters 600
500
ng/
400 IV
mL
• AUC, volume of distribution,
300 oral
200
100
half-life, Cmax, clearance,
0
0 2 4 6 8 10 12 14 16 18 20 22 24
Time (hr)
bioavailability
Active Metabolite
10000
Test Material Requirements
8000
ng/ 6000 IV
mL
oral
4000
• Limited amount 2000
0
0 2 4 6 8 10 12 14 16 18 20 22 24
• Radiolabel not necessary Time (hr)

8. Integration of Biology and Chemistry
• Saltability
• Crystallinity
- HS-PLM, XRD, DSC, TGA
• Hygroscopicity
- Hydration states
• Solubility
• Stability
• Polymorphism
• Powder Properties

9. Why is this a Problem?
Physical-chemical
•
properties of each
form are different Solubility
•
Dissolution Rate
•
The intermolecular
•
Chemical Stability
forces in a solid •
contribute to the Physical Stability
•
properties of the solid
Processability
•
Rate of Elimination
•
Bioavailability
•

10. Animal Models
In Vivo Efficacy
• Anti-infective
• Anti-cancer
• Anti-inflammation
• Others
• Obesity
• Diabetes
• Gene Therapy
Work with Clients to Customize Models
Dedicated BSL-2 Animal Rooms

11. Animal Models of Infection
(Anti-Infective)
Infectious agent introduced & the ability of the drug candidate
to relieve the experimental disease process is evaluated
• Thigh Infection Model – bacterial agents (mouse or rat)
Neutropenic animal, end points and target tissues
Antimicrobial efficacy of the drug candidate – plate count data CFU/gram
thigh tissue
Pharmacokinetics
Clinical pathology
• In Vitro Assay Support
• Minimum inhibitory concentration, minimum bactericidal
concentration, time-kill kinetic assays

12. Animal Models of Infection
(Anti-Infective)
An infectious agent is introduced and the ability of
the drug candidate to relieve the experimental
disease process is evaluated
• Mouse Sepsis Model – Staphylococcus aureus (MSSA
and MRSA), S. pneumonia, E. Coli, P aeruginosa,
Candida albicans (anti-fungal)
– End points and target tissues
100
90
80
70
---- Infectedcontrol
control
Infected
---- Vancomycin
60 Vancomycin
% survival
---- TA-1 (solution)
REP0897 (solution)
50
---- TA-1 (suspension)
REP0897 (suspension)
REP0318 (solution)
---- TA-2 (solution)
40
REP0318 (suspension)
---- TA-2 (suspension)
30
20
10
0
-1 5 11 17 23 29 35
Day

13. Oncology Screening Models
(Anti-cancer)
In Vivo Anti-tumor Assays (Xenograft models)
• Severe combined immunodeficient (SCID) mice, single subcutaneous
injection x 7 day for tumor induction followed by drug candidate dosing
by applicable route and dose levels x 7 days.
Currently established tumor models at Ricerca:
Cell Line Species Cancer Type
C-33A human cervical
Ramos human B lymphocyte
PC-3 human prostate
A-549 human lung, non-small cell
HL-60 human leukemia, PML
B16-F0 mouse melanoma
• End points - tumor size, histopathology of the induced lesion, clinical
pathology
• Pharmacokinetics

14. Oncology Screening Models
(Anti-cancer)
In Vitro Assays
• Anti-proliferation
• Acute cytotoxicity – lethality or induction of apoptosis
100 100
80 80
% Inhibition
% Inhibition
60 60
40 40
20 20
0 0
-200.10 1.00 10.00 100.00 1000.00
-200.10 1.00 10.00 100.00
Conc (!M)
Conc (!M)

15. Anti-Inflammation Model
An acute efficacy screening model to evaluate impact
on the inflammatory response:
LPS Induction of TNF! Release in Balb-c Mice
• Drug candidate administered orally, intraperitoneal, sub-cutaneously
• Lipopolysaccharide (LPS) dosed IP - optimized to provide maximal
release of TNF!
• End points – serum/plasma TNF! by ELISA
– Pharmacokinetic satellite group
– Biomarkers

16. Effect on LPS Induced TNF! Release in Mice
by Single Oral Dose of Test Article
Percent reduction from LPS control
100%
90%
1 hour
80%
between
70% oral dose
60% and LPS
dose
50%
4 Hours
40% between
30% oral dose
and LPS
20%
dose
10%
0%
0
0
,10
0
0
2, 1
4, 1
1,1
3,1
PC
TA
TA
TA
TA
Test Article dosed and dose administered (mg/kg)

17. Summary
• Animal models screen drug candidates for potential
therapeutic efficacy
• Confounded by species of animal, metabolism,
pharmacokinetics, organ system anatomy, and
physiology
• An initial opportunity to integrate biology and
chemistry
• Anti-infectivity models
• Anti-tumor assays
• Anti-inflammatory models

18. Thank you!
Ricerca Contacts
Ann L. O’Leary, Ph.D.
Manager, Animal Models/Microbiology
440-357-3561
oleary_a@ricerca.com
Prabu Devanesan, Ph.D.
Manager, In Vitro DMPK
440-357-3106
devanesan_p@ricerca.com
Andrea Hubbell
Scientist, In Vitro DMPK
440-357-3753
hubbell_a@ricerca.com

19. Biology Services
Randy Jones, D.V.M., Ph.D.
Diplomate A.B.V.T. & A.B.T.
Vice President Biology Services
Ricerca Biosciences, LLC
February 5, 2007