FDA guidance for industry on bioavailability studies submitted in NDAs or INDs

The US Food and Drug Administration has issued a  final guidance to drug sponsors on conducting and submitting bioavailability (BA) studies for drug products in investigational new drug applications (INDs), new drug applications (NDAs), and NDA supplements.

Determining the BA of formulations is important during the life cycle of drug products and aids in the FDA’s evaluation of the safety and effectiveness of a product in an IND, NDA, or NDA supplement, the agency noted. To determine the safety and efficacy of a drug product for the proposed indication, the FDA reviews all submitted information, including BA data, exposure-response evaluations, and clinical trial results.

This guidance contains recommendations on how to meet the BA requirements set forth in 21 CFR part 320 as they apply to dosage forms intended for oral administration. These dosage forms include tablets, capsules, solutions, suspensions, conventional (eg, immediate-release (IR) drug products) and modified-release (MR) (eg, extended-release (ER), delayed-release (DR)) drug products.