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Handling and Retention of Bioavailability BA and Bioequivalence BE Testing Samples Draft Guidance for Industry March 2024

Draft Level 1 Guidance

Not for implementation. Contains non-binding recommendations.

This guidance is being distributed for comment purposes only.

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Although you can comment on any guidance at any time (see 21 CFR 10.115(g)(5)), to ensure that the FDA considers your comment on a draft guidance before it begins work on the final version of the guidance, submit either online or written comments on the draft guidance before the close date.

If unable to submit comments online, please mail written comments to:

Dockets Management
Food and Drug Administration
5630 Fishers Lane, Rm 1061
Rockville, MD 20852

All written comments should be identified with this document's docket number: FDA-2002-D-0176

Docket Number:
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Guidance Issuing Office
Center for Drug Evaluation and Research

This guidance is intended to provide recommendations for study sponsors and/or drug manufacturers, contract research organizations (CROs), site management organizations (SMOs), clinical investigators, and independent third parties regarding the procedure for handling reserve samples from relevant bioavailability (BA) and bioequivalence (BE) studies, as required by 21 CFR 320.38 and 320.63. The guidance highlights (1) how the test article and reference standard for BA and BE studies should be distributed to the testing facilities, (2) how testing facilities should randomly select samples for testing and material to maintain as reserve samples, and (3) how the reserve samples should be retained. The guidance also clarifies and emphasizes points addressed in §§ 320.38 and 320.63.

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