USA – Guidance : Quantity of Bioavailability and Bioequivalence Samples Retained Under 21 CFR 320.38(c)

This guidance describes FDA’s compliance policy related to the retention of reserve samples of the test article and reference standard used in an in vivo bioavailability (BA) and in vivo or in vitro bioequivalence (BE) study. Specifically, this guidance:

• Addresses the requirement at 21 CFR 320.38(c) to retain reserve samples of sufficient
quantity to permit FDA to perform five times all the release tests required in an
application or supplemental application

• Describes the conditions under which the Agency does not generally intend to take
enforcement action against an applicant or contract research organization (CRO) for
retaining less than the quantity of reserve samples of the test article and reference
standard that were used in the BA or BE study as specified in 21 CFR 320.38(c)…