Implementing the Biopharmaceutics Classification System in Drug Development: Reconciling Similarities, Differences, and Shared Challenges in the EMA and US-FDA-Recommended Approaches

The US-FDA recently posted a draft guideline for industry recommending procedures necessary to obtain a biowaiver for immediate-release oral dosage forms based on the Biopharmaceutics Classification System (BCS). This review compares the present FDA BCS biowaiver approach, with the existing European Medicines Agency (EMA) approach, with an emphasis on similarities, difficulties, and shared challenges. Some specifics of the current EMA BCS guideline are compared with those in the recently published draft US-FDA BCS guideline. In particular, similarities and differences in the EMA versus US-FDA approaches to establishing drug solubility, permeability, dissolution, and formulation suitability for BCS biowaiver are critically reviewed. Several case studies are presented to illustrate the (i) challenges of applying for BCS biowaivers for global registration in the face of differences in the EMA and US-FDA BCS biowaiver criteria, as well as (ii) challenges inherent in applying for BCS class I or III designation and common to both jurisdictions.

Impact of data base structure in a successful in vitro-in vivo correlation for pharmaceutical products

The in vitro-in vivo correlation (IVIVC) (Food and Drug Administration 1997) aims to predict performances in vivo of a pharmaceutical formulation based on its in vitro characteristics. It is a complex process that (i) incorporates in a gradual and incremental way a large amount of information and (ii) requires information from different properties (formulation, analytical, clinical) and associated dedicated treatments (statistics, modeling, simulation). These results in many studies that are initiated and integrated into the specifications (quality target product profile, QTPP). This latter defines the appropriate experimental designs (quality by design, QbD) (Food and Drug Administration 2011, 2012) whose main objectives are determination (i) of key factors of development and manufacturing (critical process parameters, CPPs) and (ii) of critical points of physicochemical nature relating to active ingredients (API) and critical quality attribute (CQA) which may have implications in terms of efficiency, safety, and inoffensiveness for the patient, due to their non-inclusion. These processes generate a very large amount of data that is necessary to structure. In this context, the storage of information in a database (DB) and the management of this database (database management system, DBMS) become an important issue for the management of projects and IVIVC and more generally for development of new pharmaceutical forms. This article describes the implementation of a prototype object-oriented database (OODB) considered as a tool, which is helpful for decision taking, responding in a structured and consistent way to the issues of project management of IVIVC (including bioequivalence and bioavailability) (Food and Drug Administration 2003) necessary for the implementation of QTPP.

Novel bioequivalence approach for narrow therapeutic index drugs

Narrow therapeutic index drugs are defined as those drugs where small differences in dose or blood concentration may lead to serious therapeutic failures and/or adverse drug reactions that are life-threatening or result in persistent or significant disability or incapacity. The US Food and Drug Administration proposes that the bioequivalence of narrow therapeutic index drugs be determined using a scaling approach with a four-way, fully replicated, crossover design study in healthy subjects that permits the simultaneous equivalence comparison of the mean and within-subject variability of the test and reference products. The proposed bioequivalence limits for narrow therapeutic index drugs of 90.00%-111.11% would be scaled based on the within-subject variability of the reference product. The proposed study design and data analysis should provide greater assurance of therapeutic equivalence of narrow therapeutic index drug products.

FDA evaluations using in vitro metabolism to predict and interpret in vivo metabolic drug-drug interactions: impact on labeling

Recent advances in in vitro metabolism methods have led to an improved ability to predict clinically relevant metabolic drug-drug interactions. To address the relationships of in vitro metabolism data and in vivo metabolism outcomes, the Office of Clinical Pharmacology and Biopharmaceutics in the Center for Drug Evaluation and Research, Food and Drug Administration, evaluated a number of recently approved new drug applications. The goal of these evaluations was to determine the contribution of in vitro metabolism data in (1) predicting in vivo drug-drug interactions, (2) determining the need to conduct an in vivo drug-drug interaction study, and (3) incorporating findings into drug product labeling. Ten cases are presented in this article. They fall into two major groups: (1) in vitro data were predictive of in vivo results, and (2) in vitro data were not predictive of in vivo results. Discussion of these cases highlights factors limiting predictability of in vivo metabolic interactions from in vitro metabolism data. The integration of these findings into drug product labeling is also discussed.