Critique et développement des modèles pré-cliniques de safety

Transcription

1 Critique et développement des modèles pré-cliniques de safety DIU FARC-TEC Hôpital Saint Antoine, 13 octobre 2014 Philippe G Detilleux, DVM, PhD, Diplomate ACVP Global Deputy, Preclinical Safety Disposition, Safety & Animal Research (philippe.detilleux@sanofi.com)

2 La Toxicologie Réglementaire dans le développement des médicaments Introduction Contexte réglementaire Les études réglementaires : Toxicologie génétique Pharmacologie de sécurité Toxicologie générale Toxicologie de la reproduction Les Produits Biologiques et Anti-cancéreux Le dossier pré-clinique: DIU FARC-TEC, Oct

3 Le médicament n'est pas un produit anodin DIU FARC-TEC, Oct

4 Des incidents graves qui ont marqué les mémoires Médicaments Thalidomide Distilbène quinolones cérivastatine Effets indésirables Effets tératogènes Atteintes génitales de la descendance Risques imprévus de ruptures tendineuses Atteintes musculaires graves > décès Mais des milliers de médicaments dont on n entend jamais parler DIU FARC-TEC, Oct

5 Pourquoi n importe quel médicament peut devenir dangereux? L action thérapeutique du médicament est un ensemble de paramètres indissociables Sous dosage =pas d'action La dose Bon dosage =action optimale La durée Sur dosage =toxicité Le métabolisme de l'individu De multiples interactions chimiques non identifiables a priori DIU FARC-TEC, Oct

6 La toxicité est-elle liée à une exacerbation de l effet pharmacologique? Augmentation dose NON (ex: acétaminophène) Action pharmacologique Action toxicologique Marge de sécurité Cas intermédiaires (ex: aspirine) Action Action pharmacologique toxicologique OUI (ex: cytotoxiques anticancéreux) Action pharmaco- & toxicologique Pas de marge de sécurité DIU FARC-TEC, Oct

7 From hazard identification to risk assessment HAZARD VERSUS RISK 1) Hazard identification 3) Dose-response and exposure 5) Risk characterization 2) Hazard characterization 4) Quantitative analysis 6) Risk assessment DIU FARC-TEC, Oct

8 From hazard identification to risk assessment HAZARD VERSUS RISK 1) Hazard identification 3) Dose-response and exposure 5) Risk characterization 2) Hazard characterization 4) Quantitative analysis 6) Risk assessment DIU FARC-TEC, Oct

9 Evaluation de la sécurité des médicaments utilisation de modèles in vitro et in vivo pour éviter les effets adverses chez l homme et obtenir l approbation réglementaire DIU FARC-TEC, Oct

10 Evaluation de la sécurité du médicament Un ensemble d études aux objectifs spécifiques Toxicité générale Effets sur les grandes Fonctions vitales Potentiel d abus (Safety Pharmacology) Toxicologie génétique Carcinogenicité Toxicité de la reproduction Toxicité locale Immuno-toxicité Phototoxicité DIU FARC-TEC, Oct

11 Un ensemble de textes réglementaires Les guidelines (ICH, FDA, EMEA, OECD, MHW, etc ) Les Bonnes Pratiques de Laboratoire (BPL) Accréditation des installations d essai (inspections) Définition et respect de procédures opératoires Documentation de toutes les activités Le Respect de l Éthique Animale Les études sont revues par un comité d éthique Respect de la règle des 3 R (Remplacement, Raffinement, Réduction) Anticipation de la douleur et détresse animale et définition de critères d évaluation Respect et adaptation aux nouvelles normes en matière d hébergement animal Maintient des animaux en groupes Enrichissement des animaux Surface des animaleries Accréditation (e.g. AAALAC) DIU FARC-TEC, Oct

12 Regulatory Environment Regulatory agencies and other bodies implicated FDA U.S. Government agency (Food and Drug Administration) CDER : Center for Drug Evaluation and Research CBER : Center for Biologics Evaluation and Research EMEA European Agency for the Evaluation of Medicinal Products CPMP : Committee for Proprietary Medicinal Products AFSSAPS French Regulatory Agency PMDA Japanese Government Agency (Ministry of Health and Welfare) OECD (OCDE) Organization for Economic Cooperation and Development ICH International Conference on Harmonization DIU FARC-TEC, Oct

13 Preclinical Regulatory Guidelines General considerations Guidelines provide an outline of the strategy to be applied Harmonization across regions Consistency Transparency Deliberately not specifically detailed documents Flexibility/ Rigidity Open to interpretation Guidelines are guides (not strict requirements) to achieve a wellargued non-clinical development needed to support clinical development and marketing authorization Good scientific reasons not to follow a guideline, do it but justify it explicitly In case of doubt, scientific advice can always be requested DIU FARC-TEC, Oct

14 Preclinical Regulatory Guidelines List of guidelines General guidelines Non-Clinical Safety Studies For The Conduct Of Human Clinical Trials For Pharmaceuticals (ICH M3[R2]) Strategies to identify and mitigate risks for first-in-human clinical trials with investigational medicinal products (EMEA/CHMP/SWP/28367/07) Pharmacology Safety pharmacology studies for human pharmaceuticals (ICH S7A) The nonclinical Evaluation of the potential for delayed Ventricular Repolarization (QT Interval Prolongation) by Human Pharmaceuticals (ICH S7B) Pharmacokinetics Toxicokinetics: the assessment of systemic exposure in toxicity studies (ICH S3A) Pharmacokinetics: Guidance for repeated dose tissue distribution studies (ICH S3B) Pharmacokinetics and metabolic studies in the safety evaluation of new medicinal products in animals (3BS11a) Safety Testing of Drug Metabolites FDA February 2008 Evaluation of control samples for non-clinical safety studies: Checking for contamination with the test substance (CPMP/SWP/1094/04 ) Toxicology - General toxicity Guideline on repeated dose toxicity (CPMP/SWP/1042/99 Rev 1 Cor) Duration of chronic toxicity testing in animals (rodent and non-rodent toxi. testing) (ICHS 4A) DIU FARC-TEC, Oct

15 Preclinical Regulatory Guidelines Genotoxicity Guidance on Genotoxicity Testing and Data Interpretation for Pharmaceuticals intended for Human use (ICH S2 (R1)) Specific aspects of regulatory genotoxicity tests for pharmaceuticals (ICHS2A) Genotoxicity: a standard battery for genotoxicity testing of pharmaceuticals (ICHS2B) Mutagenic impurities replaced (ICH M7 draft) Carcinogenicity Need for carcinogenicity studies of pharmaceuticals (ICH S1A) Testing for carcinogenicity of pharmaceuticals (ICH S1B) Dose selection for carcinogenicity studies of pharmaceuticals (ICH S1C (R2)) Reproductive toxicology Detection of toxicity to reproduction for medicinal products including toxicity to male fertility (ICHS 5A) Risk Assessment of Medicinal Products on Human Reproduction and Lactation: From Data to Labelling Need for Non-Clinical Testing in Juvenile Animals on Human Pharmaceuticals for Paediatric Indications Local tolerance Non-clinical local tolerance testing of medicinal products (CPMP/SWP/2145/00) Other toxicity List of guidelines (cont d) Non-clinical guideline on drug-induced hepatotoxicity (CHMP/SWP/150115/06) Non-Clinical Investigation of the Dependence Potential of Medicinal Products (CHMP/SWP/94227/04) Immunotoxicity studies for Human Pharmaceuticals (ICH S8) Photosafety evaluation of pharmaceuticals (ICH S10 draft Step 1) Replacement of animal studies by in vitro models (CPMP/SWP/728/95) DIU FARC-TEC, Oct

16 Specific guidelines Anticancer drugs: Preclinical Regulatory Guidelines List of guidelines (cont d) Non-clinical evaluation for anticancer pharmaceuticals (ICH S9) Gene therapy Non-clinical studies required before first clinical use of gene therapy medicinal products (CHMP/GTWP/125459/2006 ) Fixed-dose combination Non-clinical development of fixed combinations of medicinal products (CHMP/SWP/258498/05 ) Vaccines Pre-clinical pharmacological and toxicological testing of vaccines (CPMP/SWP/465/95) Biologics Pre-clinical safety evaluation of biotechnology-derived pharmaceuticals (ICH S6 R1) Comparability of medicinal products containing biotechnology-derived proteins as active substance - Annex on non-clinical and clinical issues (CPMP/3097/02 ) DIU FARC-TEC, Oct

17 L évaluation de la sécurité des médicaments au cours du développement Entry in Development Discovery Discovery Genetic Tox Screening Exploratory Safety Pharm. GLP batch Core Safety Pharmacology Entry in Clinics PHARMACEUTICAL DEVELOPMENT Preclinical Phases Genetic Toxicity Development Ph. I Clinical Phases Ph.II DALA Assessement Pharmacovigilance Ph. III (safety/efficacy) Submission Ph. IV Exploratory Tox Dose -range studies Acute Tox 1 month Tox Chronic (3/6 month) Tox Carcinogenicity Dose Range Teratology Dose ranging Fertility Teratology Male Fertility Female Fertility Mechanistic studies (case by case) Peri- Post Natality MPK support DIU FARC-TEC, Oct

18 La Toxicologie Génétique DIU FARC-TEC, Oct

19 Toxicologie génétique = Evaluation des interactions avec l ADN: Comment? Utilisation d une batterie de test: Two end-points GENE CHROMOSOME Both in vitro and in vivo BACTERIA RODENTS MAMMALIAN CELLS DIU FARC-TEC, Oct

20 Standard First-in-Human Battery of GLP Genotoxicity Tests IN VITRO IN VIVO GENE MUTATIONS CHROMOSOME DAMAGE BACTERIA MAMMALIAN CELLS MAMMALIAN CELLS AMES TEST Salmonella typhimurium strains: TA1535 TA1537 TA98 TA100 TA102 and / or Escherichia coli In vitro CHROMOSOME ABERRATION TEST in human lymphocytes or cell lines (CHO, V79) or MOUSE LYMPHOMA ASSAY (thymidine kinase locus) on L5178Y cell line In vivo MICRONUCLEUS or In vivo CHROMOSOME ABERRATION TEST In rat or mouse bone marrow or peripheral blood DIU FARC-TEC, Oct

21 Follow-up in Case of Positive Results in the GLP Battery (with the exception for treatment of life-threatening diseases) GENE MUTATIONS CHROMOSOME DAMAGE IN VITRO BACTERIA MAMMALIAN CELLS MAMMALIAN CELLS AMES TEST (No Go if positive) In vitro MOUSE LYMPHOMA ASSAY Or as appropriate, in vitro CHROMOSOME ABERRATION TEST IN VIVO In vivo MICRONUCLEUS TEST (No Go if positive) Not always a No Go if positive but in case of clearly positive results additional studies needed: to confirm the absence of effect in vivo, to confirm the absence of direct interaction with DNA, to explain the indirect effect on DNA (mechanistic studies) Moreover, risk assessment (weight-of-evidence approach) should be discussed, and the potential impact on registration should be evaluated DIU FARC-TEC, Oct

22 Other Considerations for Development on revision to ICH S2 [now S2(R1)] Options for standard battery Some other changes High dose for mammalian cells now 1 mm instead of 10 mm Can evaluate in vivo genetox in repeatdose studies No duplication assay needed in Ames test Changes to acceptance criteria in in vitro tests Only on gender for in vivo assay OPTION 1 In vitro mammalian cell test Negative or not relevant Positive in vivo Micronucleus test Preferably Integrated Gene Mutation test in bacteria Positive in vivo Micronucleus test PLUS 2nd in vivo endpoint/tissue (comet) Acute or integrated OPTION 2 No in vitro mammalian cell test in vivo Micronucleus test PLUS 2nd in vivo endpoint/tissue (COMET Assay) Acute or integrated DIU FARC-TEC, Oct

23 Principe du test de Ames Mutated bacteria Deficient for histidine synthesis Reverse mutation Wild type bacteria Proficient for histidine synthesis Salmonella typhimurium strains: TA1535 Base-pair substitution TA100 (guanine-cytosine) Revertant colonies selected on agar plates containing low level of histidine (to allow 1-3 divisions) TA102 Base-pair substitution (adenine-thymine) TA1537 Frameshift mutation TA98 resulting from base insertion or deletion Cytotoxicity evaluation: inhibition of background growth, decrease in the number of spontaneous revertant colonies DIU FARC-TEC, Oct

24 Principe du Mouse Lymphoma Assay (MLA) L5178Y TK +/- cells (thymidine kinase) trifluorothymidine sensitive Chromosome damage and/or gene mutations L5178Y TK -/- mutant cells trifluorothymidine resistant selected in culture medium containing trifluorothymidine as selective agent In culture medium containing trifluorothymidine, Only TK -/- mutant cells survive. Cytotoxicity parameters: decrease relative total growth (RTG) RTG: cell loss during treatment x cell growth on day 1 and 2 x cloning efficiency at the time of mutant cell selection Clone of mutant cells DIU FARC-TEC, Oct

25 Principe du test d abération chromosomique Human lymphocytes or Cell lines (e.g. V79, CHO) Chromosome damage In metaphase arrested cells: Scoring of structural chromosome aberrations Deletions: breaks Exchanges: rearrangements Reporting of numerical chromosome aberrations Polyploid cells or cells with endoreduplicated chromosomes Cytotoxicity parameters: decrease in mitotic index cell counts or cell confluency DIU FARC-TEC, Oct

26 Les tests du micro-noyaux Structural damage acentric fragment Mammalian cell without cytochalasine B Micronucleated cells Chromosome non-disjunction Mammalian cell with cytochalasine B Inhibition of cytokinesis Lagging chromosome Numerical damage DIU FARC-TEC, Oct

27 Pharmacologie de Sécurité DIU FARC-TEC, Oct

28 Pharmacologie de Sécurité Testing System Purkinje Fibers herg Physiological function tested In vitro assay for cardiac safety assessment In vitro assay for cardiac safety assessment Cardiovascular Study in Dogs (telemetry and/or anesthetized) Respiratory In vivo assay for cardiac safety assessment In vivo assay for respiratory safety assessment Irwin Test in Rodents Locomotor Activity in Rodents Proconvulsivant activity Renal Gastrointestinal System General behavior in vivo Neuromuscular assessment in vivo Coupled with body temperature assessment CNS assessment in vivo Assessment of renal function in vivo Assessment of several endpoints (e.g. transit time, ulceration potential) DIU FARC-TEC, Oct

29 SAFETY PHARMACOLOGY : Central Nervous System BEHAVIOUR CHANGES (modified Irwin profile) (1) Autonomic functions (2) Awareness (3) Motor activity (4) Motor coordination and tone LOCOMOTOR ACTIVITY Recording of exploratory and non exploratory locomotor activity Assess any myorelaxant/sedative effects of a drug substance DIU FARC-TEC, Oct

30 SAFETY PHARMACOLOGY : Respiratory System WHOLE BODY PLETHYSMOGRAPHY DIU FARC-TEC, Oct

31 SAFETY PHARMACOLOGY Cardiovascular System In vitro test : herg assay (CHO cells) Action potential in rabbit Purkinje fibers In vivo test : ECG in conscious telemetered animal (dog, NHP) DIU FARC-TEC, Oct

32 History of terfenadine: the drug that changed everything Approved in 1982 Inhibiting the metabolism leads to higher plasma levels that are linked to increases in QT/QTC and eventual fatal TdP No problems at therapeutic dose, however, the product is metabolised by CYP 3A4 Torsades de Pointes Occurring in Association with Terfenadine Use Monahan, MD, et al. JAMA Vol, 264 Dec Terfenadine-Ketoconazole Interaction Pharmacokinetic and Electrocardiographic Consequences Honig, MD, et al. JAMA Vol. 269 March 1993 Lessons learned Not only cardiovascular drugs cause TdP Need to know about metabolism to assess risk DIU FARC-TEC, Oct

33 Other Drugs Soon Withdrawn Due to QT/TdP Issues Posicor (mebefradil) Raxar (grepafloxacin) Hismanal (astemizole) Propulsid (cisapride) In addition, many other drugs have received warning labels and restrictions on their use due to QT/TdP concerns DIU FARC-TEC, Oct

34 QT: Opportunity to move from risk factor to molecular mechanism Whole heart electrical activity =ECG Delayed repolarization QT prolongation herg Cell electrical activity = Action Potential Delayed repolarization APD increase Abnormal automaticity EAD s Membrane electrical activity = current (ion channels) Target IC 50 herg DIU FARC-TEC, Oct