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GUIDANCE DOCUMENT

Safety Testing of Drug Metabolites November 2016

Download the Final Guidance Document
Final Level 2 Revised Guidance
Docket Number:
FDA-2008-D-0065
Issued by:
Guidance Issuing Office
Center for Drug Evaluation and Research

[updated March 5, 2020]

This guidance provides recommendations to industry on when and how to identify and characterize drug metabolites whose nonclinical toxicity needs to be evaluated. Drug metabolites may need to be determined in nonclinical studies when they are disproportionate drug metabolites, that is, metabolites identified only in humans or present at higher plasma concentrations in humans than in any of the animal species used during standard nonclinical toxicology testing.

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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-2008-D-0065.

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