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Interpreting Sameness of Gene Therapy Products Under the Orphan Drug Regulations Guidance for Industry September 2021

Docket Number:
Issued by:
Guidance Issuing Office
Center for Biologics Evaluation and Research
Office of the Commissioner, Office of Clinical Policy and Programs, Office of Orphan Products Development

This guidance provides FDA’s current thinking on determining sameness of human gene therapy  products under FDA’s orphan drug regulations for the purpose of orphan-drug designation and orphan-drug exclusivity.  This guidance is intended to assist stakeholders, including industry and academic sponsors who seek orphan-drug designation and orphan-drug exclusivity, in the development of gene therapies for rare diseases.  This guidance focuses specifically on factors that FDA generally intends to consider when determining sameness for gene therapy products and does not address sameness determinations for other types of products.  This guidance finalizes the draft guidance of the same title dated January 2020.

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-2019-D-5392 .

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