PBPK Modeling to Support Bioavailability and Bioequivalence Assessment in Pediatric Populations.

This report summarizes the proceedings for Session 3 of the one-day public workshop entitled "Advances in PBPK Modeling and its Regulatory Utility for Oral Drug Product Development" a jointly sponsored workshop by U.S. Food and Drug Administration (FDA) and the Center for Research on Complex Generics (CRCG) on October 12, 2023. The theme of this session was the application and relevant considerations for PBPK modeling in supporting bioavailability (BA) and BE assessment in pediatric populations. The takeaway message from this session was that PBPK modeling can support relative BA and BE assessment in pediatrics since such studies are generally performed in adults or healthy subjects. PBPK absorption modeling can incorporate characteristics of the drug substance and formulation as well as pediatric physiology to assess the potential differences in absorption of different formulations in pediatrics for new and generic drugs. It is necessary to consider the totality of data and use all available evidence integrated into a mechanistic PBPK model to support decision-making. Global research efforts are needed to bridge critical data gaps.