Drug Discovery and Preclinical Development

1 drug Discovery and Preclinical DevelopmentNeal G Simon Ph DNeal G. Simon, of Biological Sciences Disclaimer Thh hkl dd tdi t Those who have knowledge, don t predict. Those who predict, don t have knowledge. Lao Tzu, 6thCentury BC Chinese PoetDiscovery and Preclinical The R&D and TransformationIV. The Preclinical Development ProcessV. Case Study: Stress-related Affective DisordersSerendipity or Good Science: Building OpportunityHoffmanOsterhofI. BackgroundDrug Development ProcessBiopharmaceutical drug Development : Attrition drug DiscoveryPre-ClinicalClinical TrialsFDA ReviewLarge Scale Manufacturing/ Phase IVPhase I20100 Phase IIIubmittedubmitted250 Compounds5 Compounds10,000 Com-1 FDA Ad20-100 Volunteersase1000-5000 VolunteersIND SuNDA Su250 Compounds5 CompoundspoundsApproved DrugPhase II100-5005 years6 years2 years2 years100500 VolunteersQuelle: Burrell Report Biotechnology Industry 2006 Capitalized Cost Estimates per New Molecule*All R&D costs (basic research and Preclinical Development ) prior to initiation of clinical testing** Based on a 5-year shift and prior growth rates for the Preclinical and clinical and Grabowski (2007)II.

2 The Research & Development LandscapeppR&D Expenditures and Return on Investment: A Declining FunctionPhrma (2005); Tufts CSDD (2005)R&D Expenditures 1992-2004 and FDA ApprovalsHu et al (2007)NIH Budget by AreaPharmaceutical Industry: Diminishing Returns That is why the business model is under threat: the ability to devise new molecules through R&D and bring them to market is not keeping up with what s being lost to genericis not keeping up with what s being lost to generic manufacturers on the other end. This situation requires new thinking, new urgency, new capabilities. FdHCEOShiPlh 2005 Fred Hassan, CEO Schering-Plough, 2005 Saltzmann (2006)III. Innovation and TransformationIII. Innovation and TransformationInnovation Models and TransformationHu et al (2007)Innovation Models: In-licensing and AcquisitionsSaltzmann (2006)Me Too Drugs: Antidepressants1986 Fluvoxamine (Luvox; Solvay) SSRI1987 Fluoxetine (Prozac; Lilly) SSRI1992 Sertraline* (Zoloft; Pfizer) SSRI/NRI1993 Venlafaxine (Effexor; Wyeth) SSRI/NRI1996 Buproprion(Wellbutrin; Wyeth) SNRI/DRI1996 Buproprion(Wellbutrin; Wyeth) SNRI/DRI2002 Escitalopram (Lexapro; Forrest) SSRI2004 Duloxetine (Cymbalta; Lilly) SSRI/NRIP ersonalized Medicine (sort of) Discovery & Preclinical DevelopmentIV.

3 Discovery and Preclinical DevelopmentDiscovery and Preclinical DevelopmentLead Selection andDrug CandidatePreclinical DrugLead Selection andOptimization (iterative) drug CandidateConfirmationPreclinical DrugCharacterizationff?RegulaEfficacy Assessment: Does it work?ADME Profiling:How can it be delivered and what does the body do?atory SubmToxicology/Safety Pharmacology Assessment:Is it safe?ADME Profiling: How can it be delivered and what does the body do?mission tPharmaceutics:Is the manufacture viable and controllable?Toxicology/Safety Pharmacology Assessment: Is it safe?o FDAP harmaceutics: Is the manufacture viable and controllable?Adapted from TetraQStage 1: Lead Selection and Optimization Structural CharacterizationImpurity IdentificationEssential Pharmaceutics Impurity Identification Solubility assessment Prototype formulation Stability testingScreening Efficacy In silico profilingEarly ADMEOff ttEarly Toxicology In vitro models In vivo models OtherIn silico profiling Develop simpleanalytical method Measure membrane permeability Off target screen In vitro cytotoxicity Preliminary AMES hERG bindingpermeability Plasma StabilityAdapted from TetraQStage 2.

4 drug Candidate ConfirmationData from Lead Optimization StagePreliminary CMC(Chemistry, Manufacture and Control) Benchmark invivoModelsADME ProfilingPreliminary Toxicology Formulation for GLP ToxicologySt bilit t tiControl)Iidl Optimized analytical method Maximum tolerated dose Stability testing of active ingredient Detailed hi h il In vivo models Validated models Models in other dimethod Development Basic pharma-cokinetics (PK) &Oraltolerated dose (MTD) Repeat Dose (non-GLP) Preliminaryphysicochemical characterization Impurity analysisdisease areas& Oral Bioavailability Determine metabolism of drugPreliminary Cardiovascular Safety PharmacologydrugAdapted from TetraQStage 3: Preclinical drug CharacteristicsData from Prior StagesComprehensive ADMED etailed Preclinical CMCGLP Toxicology Package analytical method Development Comprehensive ICH Stability TestingICH iit acute study subchronic repeat dose studypPharmacokinetics GLP TK Comprehensive identification of ICH impurity analysis Develop prototype clinical formulationy Genotoxicity Battery Safety PharmacologymetabolitesgyRegulatory Submission or Presentation to PharmaAdapted from TetraQV.

5 Case Study: Stress-related Affective DisordersOverview dllllldf GPCR targeted oral small molecule drugs for stress, mood, and behavior disorders First compounds: vasopressin receptor antagonists Somewhere between skunk works, serendipity, and pygood planningAVP: Biological DiversityInvertebrate & VertebratePhysiologyVertebrate Behavior fluid regulation bhd ttbli communication lb h i carbohydrate metabolism thermoregulation sexual behavior pair bonding reproductive function paternal/maternal care social memory stress-related disorders impulsivity/violencepyHypothalamic-Pitui tary Adrenal AxisCompound #1 Profile: Novel oral vasopressin AVP receptor antagonist Initial clinical Development for stress related affective illness Serenic activity established in rodent models Market: $20+ billion World Wide Market 35 million people affected by anxiety and depression in US alone Status: Phase I completed Phase II in planningCompound #1: Preclinical DevelopmentIin vitroBiology and PKI.

6 In vitroBiology and PKII. IND-directed Toxicology and PharmacologygygyIII. Behavior and Neuroimaging* NIMH (MH063663), NIH Roadmap Initiative, NCIB inding and Function at Human AVP ReceptorA competitive binding assay was conducted in CHO cells transfected with human AVP receptor (left panel) Compound #1 inhibited AVPmediated phosphatidylAVP receptor (left panel). Compound #1 inhibited AVP-mediated phosphatidyl inositol turnover with a Ki value at nM (right panel). I hibitif HAVP Bi dibInhibition of AVP Induced IP3 ProductionInhibition of Human AVP Binding by8001000 AVP30003500EC50 = 0 87 nM400600800IC50 = nMKi = nMof Bound3H-A1500200025003000EC50 = nMKi = nMPM of3H-IP3-13-12-11-10-9-8-7-6-50200 CPM -13-12-11-10-9-8-7-6-505001000 CPConcentration: Log MConcentration: Log MCompound #1: SelectivityReceptor Class#1 Tested at vs 64 receptors including 35 GPCRsReceptor Class#1 (% inhibition)Vasopressin ittltd20% t +20%Neurotransmitter related-20% to +20%Steroids-20% to +20%Ion channels-20% to +20%Second messengers-20% to +20%Prostaglandins-20% to +20%Gthft/h20% t +20%Growth factors/hormones-20% to +20%Brain/gut peptides (not including Vasopressin 1)-20% to +20%Enzymes-20% to +20%*-20% to +20% is considered baseline, which is defined as inactive Compound #1.

7 IND-Directed Studies GeneticSafetyMammalianGenetic ToxicologySafetyPharmacologyMammalian Toxicology AMES hERG 7-day Repeat Oral AMES Chromosomal Aberration hERG Rat Irwin 7-day Repeat Oral (gavage) in Rats 28-day Repeat Oral Cardiovascular & Pulmonary Safety in Dogs (gavage) dose in Rats 7-day DRF in Dogs 28-day Repeat Oral (capsule) dose in Dogs (just completed)Compound #1: hERG Test for QT ProlongationValues shown are Inhibition of Current (%) +SEMTest Compound % Inhibition SEMC ompound (tf di60M)(terfenadine60 nM)Conducted by ChanTest, Inc; Covance GLP study 7252-117 Results: IC50 = M indicating low risk of cardiac arrhythmias based on anticipated clinical dosingCompound #1 Blocks Vasopressin-induced Increases in Blood PressureBlood Pressure2025m Hg)Blood Pressure2025m Hg)1015ssure (mm**1015ssure (mm**510lood pres**510lood pres**0vehicle Only (mg/kg)BDose (mg/kg)** p< vs vehicleVasopressin is Linked to Stress-related DisordersR.

8 Landgraf (2006). Involvement of the vasopressin system in stress-related disorders. CNS & Neurological Disorders drug Targets 5, 167-179 Increased synthesis, content, and release of AVP in PVN in HAB and LAB rats under basal conditionsElevated Vasopressin is Linked to Stress-related Disorders: Rodent ModelAVP in the paraventricular nucleus (PVN) flanking the 3rd ventricle (3V) inAVP in the paraventricular nucleus (PVN) flanking the 3rd ventricle (3V) in HAB (high anxiety) and LAB (low anxiety) Plus MazeForced Swim TestBunck et al. (2009)AVP mRNA in Supraoptic and Paraventricular Nuclei from Depressed and Control IndividualsMeynen et al (2006)Signal on film in SON and PVNAVP mRNA in PVN and SON in depressed (n=9) and control patients (n=8)fMRI: Imaging Stress/Arousal in Awake AnimalsPiloerection is an index of autonomic activationPiloerection is an index of autonomic activationCompound #1 Blocks Stress & Arousal: Composite ViewMate/Intruder + Compound #1 Imaging on awake ratsCompound #1: Blockade of Stress/Arousal in Major Brain RegionserAmygdalaCortexHippocampusThalam us& IntrudeMate ent TreatmActivation of Olfactory and Reward Pathways in the Presence of Compound #1 but not FluoxetineSerendipity or Good Science: Building OpportunityHoffmanOsterhofThanks for Your Time and Attentio