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Bioavailability Studies Submitted in NDAs or INDs – General Considerations April 2022

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

This guidance provides recommendations to sponsors and applicants2 submitting bioavailability (BA) information for drug products in investigational new drug applications (INDs), new drug applications (NDAs), and NDA supplements. 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 (e.g., immediate-release (IR) drug products) and modified-release (MR) (e.g., extended-release (ER), delayed-release (DR)) drug products. The guidance is also applicable to non-orally administered drug products when it is appropriate to rely on systemic exposure measures to determine the BA of a drug (e.g., transdermal delivery systems and certain vaginal, rectal, and nasal drug products). The guidance provides recommendations on conducting BA studies during the investigational period for a drug intended to be submitted for approval in an NDA and bioequivalence (BE) studies during the postapproval period for certain changes to drug 
products with an approved NDA.

Submit Comments

You can submit online or written comments on any guidance at any time (see 21 CFR 10.115(g)(5))

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-2018-D-4367.

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