Impact of Modeling and Simulation on Generic Drug Development and Review

Transcription

1 Impact of Modeling and Simulation on Generic Drug Development and Review Robert Lionberger, Ph.D. Director Office of Research and Standards Office of Generic Drugs Center for Drug Evaluation and Research, FDA OrBiTo OPEN Science Day Beyond BCS based biowaivers July 1, 2015

2 2 Disclaimer The views expressed in this presentation are those of the speaker and not necessarily those of the Food and Drug Administration (FDA).

3 Impact of Generic Drugs 3

4 4 What is the Science of Equivalence? Science of bridging product A works as well as product B Generic drugs are affordable because we usually do not repeat clinical studies in patients Generic drugs are intended to be used by patients The science of therapeutic equivalence is to combine In vivo and in vitro performance data Product design Patient characteristics and product use To ensure successful generic substitution

5 5 New Office of Research and Standards within OGD Division of Therapeutic Performance (DTP) Facilitates pre-anda development of generic drugs Conducts and promotes regulatory science research to establish standards to ensure therapeutic equivalence of generic versions of drug products. Evaluates post-approval safety, product use and bioequivalence issues with approved generic drugs. Division of Quantitative Methods And Modeling (DQMM) Establishes predictive and physiological models of drug product performance, drug absorption, drug pharmacology, and other quantitative methods to ensure generic drug equivalence. Develops new tools to analyze in vitro, pharmacokinetic, pharmacodynamics and clinical bioequivalence studies.

6 6 Core DQMM Tool Set Oral Drug Release/Absorption/PBPK Models Non-Oral Drug Release/Absorption/PBPK Models Pharmacometrics PK/PD, population models Big Data Analytics for complex mixtures, systems pharmacology, risk models, business process models, medical records, generic drug utilization Goal: Support generic drug research, policy development and regulatory decisions

7 7 Generic Drug Priority Areas Post-market Evaluation of Generic Drugs Equivalence of Complex Products Equivalence of Locally Acting Products Therapeutic Equivalence Evaluation and Standards Oral PBPK Non-oral PBPK PK/PD Big Data X X X X X X X X X X X

8 M&S in Generic Drug Evaluation Use for generics is to assess the risk that differences from a reference impact therapeutic substitutability BE guidance development pauc, e.g. zopidem,. (all consideration of pauc include simulation evaluation) Narrow Therapeutic Index drugs (NTID) classification nonlinear PK properties ANDA Review BE study design or control of critical attributes Post-marketing efficacy & safety evaluation of generic drugs Evaluate risks of potential failure mechanisms Methylphenidate, Warfarin, Nifidipine

9 ORAL ABSORPTION 9

10 10 Oral Absorption Models The context for biopharmaceutics modeling and simulations in the generic drug framework is different than from modeling and simulation in drug discovery and development Much more knowledge about drug and human PK data often available Goal: Predict Bioequivalence for Oral Formulations Applications to generic drug review BE standards for MR products (different mechanism between brand and generic) Partial AUC for multiphasic MR products Waivers of lower strength products Risk of formulation changes (particle size, polymorphic form) Locally acting GI drug bioequivalence Linkage from healthy subjects to patients

11 Factors Affecting Oral Absorption 11

12 Inputs and Outputs Drug substance and product information: Dose and dose volume Solubility vs. ph profiles logp, pka Dissolution: MR: dissolution profiles; IR: particle size and density Diffusion coefficient Permeability Metabolic kinetics PK parameters Clearance, Vd Tissue/organ parameters for physiologically based distribution and elimination models Fh, BA PK profiles Metabolite Info Physiological parameters GI transit time GI geometry GI fluid properties Enzymes/transporters distribution Blood flow Fa, Fg In vivo dissolution Drug in each cmpt Parent and metabolite PK 12

13 Example Use in Formulation Evaluation 13

14 Gaps for Oral Absorption There is a linkage between challenges in absorption modeling and simulation and IVP dissolution. Both need more data about in vivo physiology You want IVP dissolution to be the input that closes gaps in the models Gap: Improving the modeling and simulation for colon absorption to fully account for the performance of modified release dosage forms. Gap: Improving knowledge of in vivo hydrodynamics is needed to improve the models and IVP dissolution

15 Gaps for Oral Absorption Variability: For the generic drug program, simulation of a cross-over bioequivalence study is an important modeling and simulation application but current data sets and models of within subject variability for GI parameters lag the understanding of between subject variability. Formulation: The interaction of formulation variables with physiological factors is important to the design of bioequivalent formulations. This includes improved prediction of food effect, prediction of bioavailability for complex formulations and solid dispersions, and prediction of bioavailability for nano-size formulations.

16 16 GDUFA Research Studies Prediction of In Vivo Performance for Oral Solid Dosage Forms Awarded to the University of Michigan (HHSF C) The purpose of this contract is to improve prediction of in vivo performance of oral solid dosage forms. The scope includes modeling of GI fluid hydrodynamics, sampling of GI tract fluids composition and ph, novel dissolution methods and in vivo PK studies to validate model predictions. Pharmacokinetic Study of Bupropion Hydrochloride Products with Different Release Patterns Awarded to University of Michigan (HHSF C) The objectives of this contract are to conduct healthy subject pharmacokinetic studies of bupropion HCl modified release products with different release patterns and different doses. This will help FDA understand how the release pattern of bupropion HCl products and the genotype of metabolic enzyme may affect the bioequivalence conclusions across different dose strengths within one product line due to the saturation of intestinal metabolism.

17 17 GDUFA Research Studies Bioequivalence and Characterization of Generic Drugs Awarded to Vince & Associates Clinical Research, Inc. (#HHSF I). As part of the continuous monitoring of approved generics, this contract will support bioequivalence studies of approved generic drugs including bioequivalence between: (1) generic and brand methylphenidate hydrochloride extended release (ER) tablets and (2) a reference listed drug and generic warfarin sodium products from different suppliers and stored under different conditions, including real world use conditions. Research outcomes will include evaluating the use of replicate design bioequivalence studies for generic methylphenidate hydrochloride ER products and developing clinically relevant quality standards for warfarin sodium products.

18 18 GDUFA Research Studies Effect of Different Preparation Methods on the In Vitro and In Vivo Performance of Solid Dispersion Formulations Awarded to Purdue University, West Lafayette (1U01FD ). The study goal is to investigate the in vitro and in vivo performance of solid dispersion drug products originating from different manufacturing processes or polymer carriers and to assess performance consistency among batches and during storage. Study outcomes will identify critical process parameters and critical quality attributes for solid dispersion drug products originating from various preparation methods and will develop discriminating analytical methods for these drug products.

19 NON-ORAL ABSORPTION 19

20 Physiologically based absorption and PK models Drug substance Formulations In vitro performance Model In vivo performance 20 Jiang W, Kim S, Zhang X, Lionberger RA, Davit BM, Conner DP, Yu LX. Int J Pharm Oct 14;418(2):

21 21 Non-Oral Absorption Models The lack of efficient bioequivalence methods for locally acting drugs has limited the availability of generic drugs in this category. Research is focused on new bioequivalence approaches Inhalation Topical dermatological Nasal GI acting Ophthalmic Role of Models Planned project outcomes are simulation tools that capture the current understanding of the complex interplay between product attributes and human physiology and that help to develop new bioequivalence approaches for locally-acting drugs. Models that embody mechanistic absorption modeling and physiologically-based pharmacokinetics (PBPK) can be useful tools for both industry scientists and regulators to reduce the time and expense involved in determining whether a new formulation will be bioequivalent to an approved dosage form.

22 22 Funded Studies Topical and dermal absorption modeling University of South Australia, and Simcyp, LTD Ocular dosage forms PBPK modeling Simulations Plus, Inc., and CFD Research Corporation Intranasal CFD-PBPK modeling Applied Research Associates, Inc. Lung CFD-PBPK absorption modeling CFD Research Corporation PBPK modeling for complex parenteral injectables State University of New York at Buffalo

23 23 Highlights of Work in Progress Topical Dermatological Products Six coordinated grants (international: US, Europe, Australia) that include New in vivo data Manufacturing of semi-solid formulations Characterization of semi-solid formulations New PBPK modeling approaches Inhalation Products Role of dissolution, particle size and PK studies CFD modeling of deposition Ophthalmic Products Nine coordinated grants on in vitro characterization, drug release, and drug delivery modeling Nasal Products Use of PK studies alone for BE: in vitro, in vivo and modeling projects

24 24 GDUFA Research Studies Pulmonary Delivery Awarded to CFD Research Corporation (1U01FD ). A hybrid CFD model will be developed to predict particle deposition throughout the human airway. The hybrid model will be linked to PBPK and PD models to predict in vivo performance for orally-inhaled drug products. This computational tool will serve as a virtual platform to simulate drug PK/PD, optimize pulmonary drug delivery, and facilitate generic pulmonary drug development. Nasal Delivery Awarded to Applied Research Associates, Inc. (1 U01 FD ). In this proposal, PBPK absorption models will be linked to computational fluid dynamics models to simulate the delivery of sprayed droplets to the nose, the absorption of the drug through the nasal mucosa, and the systemic bioavailability of intranasal corticosteroids. Model simulations will improve our understanding of the absorption of intranasal corticosteroids under different dosing scenarios and will support and facilitate generic drug guidance and product development for nasal suspensions.

25 25 GDUFA Research Studies: Dermal Dermal absorption PBPK Models Awarded to the University of South Australia (1 U01 FD ) and Simcyp, Ltd. (1 U01 FD ). The University of South Australia project aims to develop a framework of physiologically-based absorption and pharmacokinetic models that define the interactions between the product and the skin and seek to predict drug and drug plasma/blood concentrations at the site of action. The Simcyp, Ltd. project goal is to develop a physiologically-based dermal absorption and disposition model supported by a clinical trials simulator platform model that accounts for variability and gender effects in healthy Caucasian volunteers. This model will be mechanistically enhanced and validated with reference to other races and special populations including pediatric, geriatric, and those populations with diseases, such as rheumatoid arthritis. The performance of the PBPK model and associated databases will be validated against clinical pharmacokinetics data for dermal products.

26 26 GDUFA Research Studies: Ocular Ocular delivery PBPK Models Awarded to Simulations Plus, Inc. (1U01FD ) and CFD Research Corporation (1U01FD ). The Simulations Plus award will advance the state of the art for ocular PBPK and mechanistic absorption modeling (MAM) software through a combination of expanding the existing knowledge base for ocular drug absorption and pharmacokinetics and implementing enhanced physiological models for human and animal eyes in the well-established Ocular Compartmental Absorption and Transit (OCAT ) MAM/PBPK model within the GastroPlus software program. The CFD Research grant will support high-fidelity models in the form of a parametric 2D/3D eye mesh model (human and animal), enabling simulation of various modes of delivery. The novel computational tool will simulate ocular drug delivery and its interaction locally and systemically within the whole body, thereby providing an accurate and efficient computational platform to virtually test, design, and develop generic ocular drug products.

27 M&S Impact in OGD Type N Examples ANDA Reviews CP, CC, and Other Consult Response PD modeling and simulation for budesonide nasal spray to support the selected dose for BE study. Development of BE criteria for zolpidem tartrate ER tablets Steady state simulations for risperidone long acting injection Simulation of in vivo alcohol dose dumping studies BE Guidances Regulatory Research Study Simulations for the development of BE criteria for complex drugs, HVDs and NTI drugs PK/PD modeling and simulation to determine the appropriate study design and evaluate BE between generic anti-epilepsy drugs and immunosuppressant drugs in patients. 27

28 28 M&S (PBPK) Submissions NDA PBPK ANDA Little attempt to use in submission Use in development? Two dispute resolution requests Nasal GI locally acting

29 Innovation Model for Future ANDA 29

30 30 GDUFA Regulatory Science Leap FDA is engaging with leading pharmaceutical and clinical scientists from across the world to ensure that the regulatory review of generic drugs is based on the best available science. Over 100 GDUFA related proposals were submitted and reviewed last summer Contracts/Grants ($$) And ORISE New Contracts/Grants FY2014 $22.8M 35 FY2013 $20.9M 28 FY2012 $3.6M 4 FY2011 $2.2M 3 FY2010 $3.1M 5

31 31 GDUFA Regulatory Science Impact Both FDA and Generic Industry Have a Common Customer Patients who want high quality generic products in all product categories Research leads to generic availability in all product categories Standards and post-approval monitoring build confidence in generic drug substitution Advance the science of equivalence: Prioritize tools and science that make equivalence evaluation clear and development easier Product design for human use