From Drug Discovery to IND Saving Time and Money Through Smart Study Design

Transcription

1 From Drug Discovery to IND Saving Time and Money Through Smart Study Design Stephen Madden BSc PhD CBiol FSB Head, Metabolism and Pharmacokinetics Charles River Preclinical Services, Edinburgh

2 Outline Brief overview of the stages of drug development Focus on discovery/candidate selection Focus on IND enabling studies Options for FIM Studies Summary

3 From Drug Discovery to Registration Candidate Selection to Early Clinical Trials Hit to Candidate Selection Late Stage Non-clinical and Clinical Development Successful NDA

4 Timeframe and Cost of Drug Development Discovery Research 5,000-10,000 NCEs Candidate selection Preclinical development Volunteer studies Phase I (safety & PK) Patient Studies Phase IIa/IIb (short-term tolerability, dose defining, POC) Phase III (multicentre clinical trials, long-term use) Phase IV (post marketing surveillance) 1 approved drug years billion $

5 Discovery Is the Innovation Engine and the First Stage in the Drug Development Process Target ID Validation Lead General HTS Screening / Optimization Chemistry Library Synthesis Medicinal Chemistry DMPK In Silico Assessment In Vitro Metabolism PK Efficacy Animal Models TGS HTPS Selectivity (Panel Assays) In vitro Efficacy In Vivo Efficacy Toxicology In Vitro Tox Non GLP Tox Safety Pharmacology herg Liability Bioanalysis Biomarkers, Assay Development, Bioanalytical

6 Candidate Selection Eliminating Key Liabilities In vitro/in vivo PK herg Liability Candidate Drug Genotoxicity/ Cellular toxicity Formulation Development CYP Inhibition Bioanalysis RGA Method Development

7 Genotoxicity -1 Screening genetic toxicology tests assess early indications of mutagenic potential in both bacterial and mammalian cell systems Bacterial Mutation (Ames) Chromosomal aberrations Test article requirements ca mg per test

8 Genotoxicity 2 Bluescreen assay Bluescreen assay assesses changes in expression of the GADD45a gene Detects direct acting mutagens, clastogens, aneugens, topoisomerase inhibitors and polymerase inhibitors Specificity and sensitivity for predicting genotoxic human carcinogens >95% and >80%, respectively Assay can be run ± metabolic activation Test article requirement of <10 mg

9 Screening for Lung/Inhalation Toxicity MucilAir Isolation, amplification & seeding Primary Human Cells Ready-to-use Fully differentiated Airway Epithelium Nose Trachea Bronchi Mucus Ciliated Cells Goblet Cells Basal Cells MucilAir Shelf-life of 1 year Air-Liquid interface, differentiation

10 Multiple end-points from a single test system Apical Exposure (e.g. liquids, solids, nanoparticles, gas, smoke, etc.) Information from Apical Side TEER measurement Resazurin test Cilia beating Monitoring Morphology Mucin secretion Air Liquid + Cells information RNA/DNA/Proteins Information from Culture Medium Secretion of soluble factors (cytokines/chemokines/ metalloproteinases) LDH release MucilAir is available from donors with different pathologies eg smoker, allergic rhinitis, asthma, COPD, cystic fibrosis

11 Mucilair test results 0.0 mm SDS 0.16 mm SDS 0.31 mm SDS 0.63 mm SDS 1.25 mm SDS 2.50 mm SDS

12 Assessment of Pharmacokinetics 2: In vivo studies in rodents and non-rodents Rodent Studies Various rat strains available, rats used often have vascular cannulation to assist with blood sampling Oral, IV or subcutaneous administration Non-Rodent Studies Charles River colony of Non-naïve Beagle dogs Intact males and females available Bile-duct cannulated animals available Charles River colony of Non-naïve Cynomolgus monkeys Intact males and females available

13 ng/ml METABOLITE PEAK AREA PARENT ng/ml ng/ml Example of PK Applications Compound comparison Formulation comparison Time (h) A B C D Dose route comparison Metabolite AUC hours intravenous oral intratracheal hours M1 M2 M3 PARENT

14 Assessment of Pharmacokinetics 3: Typical workflow for a PK study Friday Monday Tuesday Wednesday Friday Compound Arrival Study Set Up Preparation Formulation Administration Sampling Final Sample Collection Plasma Analysis Data Issue

15 Bioanalysis Fit for purpose assays RGA0 RGA3 Multiple species and matrices Ring fenced resources 72h Expedited assay validation PK data can be used to select/eliminate candidates

16 Metabolite trawling of PK/TK samples PK/TK Profile of Parent Drug MS/MS analysis of selected TK samples Data trawling for common biotransformations R 6 Data filtering against matrix samples M+16 M+32 M+176 M-14 etc

17 Milestones for Drug Development Clinical Candidate Selection Studies as previously described Approval for FIM Study (IND Submission) Assessment of genotoxicity Short term toxicity Safety Pharmacology Preliminary ADME? Human Efficacy and Tolerability Large Scale Clinical Trials ADME/MIST Assessment Chronic toxicity testing Carcinogenicity Assessment Reproductive/Developmental Toxicology NDA Submission Marketing Authorization Large Scale Manufacturing Alternative Formulations Post Marketing Surveillance Alternative Indications

18 Inclusion of Genotoxicity Endpoints in Repeat Dose Toxicology Studies ICH S2 (R1) - In case of repeated administrations, attempts should be made to incorporate genotoxicity endpoints into toxicity studies Incorporation of micronucleus endpoint into 14/28-day toxicology studies Measures acute response to drug exposure Pig-a gene mutation test detects mutations that cause failure of GPI anchors. X- chromosome linked Specific cell surface markers such as CD59 and CD24 not expressed Time-dependent response Environmental and Molecular Mutagenesis Volume 52, Issue 9, December 2011

19 Mutants per 10 6 cells Mutants per 10 6 cells Effect of N-ethyl-N-nitrosourea (ENU) on CD59 Cell Surface Expression Pig a Assay ENU 0 mg/kg/day ENU 20 mg/kg/day ENU 40 mg/kg/day Treatment Group Day 0 Day 15 Day 30 Day 45 Day of Treatment

20 Use of Microsampling on Toxicology Studies Well established methods for capillary microsampling Transfer technology to rodent toxicology studies Offers animal welfare benefits Improves relevance of data Data generated needs to be comparable with existing sampling methods

21 Microsampling Validation Results - EDI Plasma Methylene Blue Concentrations in Rats Following Oral Administration of 50 mg/kg Methylene Blue

22 Microsampling Validation Results - OHI Plasma Methylene Blue Concentrations in Rats Following Oral Administration of 50 mg/kg Methylene Blue

23 Microsampling Validation Results - NEV Plasma Methylene Blue Concentrations in Rats Following Oral Administration of 50 mg/kg Methylene Blue

24 Microsampling Validation Results - MTL Plasma Methylene Blue Concentrations in Rats Following Oral Administration of 50 mg/kg Methylene Blue

25 Microsampling Validation - Summary AUC(0-t) Male AUC(0-t) Female Macro Micro Ratio Macro Micro Ratio EDI % % NEV % % MTL % % OHIO % %

26 Microsampling Validation - Summary Cmax Male Cmax Female Macro Micro Ratio Macro Micro Ratio EDI % % NEV % % MTL % % OHIO % % 26

27 Toxicology Rat Study Design TK Sampling regimen: Two occasions - Day 1 and Week 13 Control 2 timepoints (Cmax and Cmin Treated groups 6 timepoints/ occasion Sampling regimen - Standard: 3M+3F/timepoint (bleeding each animal twice) Based on a ml blood sample Sampling regimen - Microsampling: all animals/timepoint Based on a 32 µl blood sample Main Study 10M+ 10F Satellite Study Standard TK Sampling Control Low Inter High 3M+3F 10M+ 10F 10M+ 10F Total number of Satellite animals = 60 Satellite Study Microsampling 3M+3F Total number of Satellite animals = 24 10M+ 10F 9M+9F 9M+9F 9M+9F 3M+3F 3M+3F 3M+3F

28 Toxicology Mouse Study Design TK Sampling regimen: Two occasions - Day 1 and Week 13 Control 2 timepoints (Cmax and Cmin Treated groups 6 timepoints/ occasion Sampling regimen - Standard: 3M+3F/timepoint (bleeding each animal once) Based on a ml blood sample (*larger vol may result in no recovery on Day 1 and so a second set of animals would be required for Week 13) Sampling regimen - Microsampling: all animals/timepoint Based on a 32 µl blood sample Main Study 10M+ 10F Satellite Study Standard TK Sampling Control Low Inter High 6M+ 6F 10M+ 10F 18M+ 18F 10M+ 10F 18M+ 18F Total number of Satellite animals = 120 (*240) Satellite Study Microsampling 3M+3F Total number of Satellite animals = 24 10M+ 10F 18M+ 18F 3M+3F 3M+3F 3M+3F

29 % administered dose Urine Faeces Recovery % administered dose Urine Faeces Recovery Preliminary ADME Study ORAL DOSING IV DOSING 168 h, 1 albino & 1 pigmented for QWBA 4, 24 & 72 h 168 h 10 min Time (h) Time (h)

30 Genetic Toxicology General Toxicology Safety Pharmacology Typical Studies Required to Support Traditional FIM Dosing (Oral NCE) Ames test Single dose and 1 week toxicity in rat herg channel test Mammalian in vitro test or an in vivo assessment of genotoxicity 28 day rat study* MTD study in dog (2 nd species) Cardiovascular study Respiratory study 28 day study in dog* (2 nd species) Irwin screen *TK assessment should be included

31 Scheduling IND-Enabling Studies

32 Genetic Toxicology General Toxicology Safety Pharmacology The Exploratory FIM Route Reduced toxicology package required to support an exploratory microdose human study SAR of genetox potential Ames test Extended single dose study in rat* (Approach ) 7 day study by iv route in rat* (Approach ) herg channel test Cardiovascular study Chromosomal aberration or mouse lymphoma test *TK assessment should be ICH M3 (R2) MTD study in dog (2 nd species) 28 day study in dog (2 nd species) Respiratory study Irwin screen

33 Relative cost and timings of FIM options Timing Cost Traditional FIM 38 weeks 350, ,000 GBP Exploratory Phase I (approach 1) Exploratory Phase 2 (approach 2) 12 weeks 40,000-45,000 GBP 12 weeks 50,000 55,000 GBP

34 Summary Identifying and evaluating potential key liabilities can facilitate early and cost effective drug attrition Combination study designs are an effective way of addressing the 3Rs and can offer cost/time savings Exploratory FIM studies can provide a cost effective route for confirming human exposure