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# Guide on Studying Multiple Gene Therapies
- URL: https://www.fdaweb.com/guide-on-studying-multiple-gene-therapies/
- Published: 2021-10-01T12:00:00.000Z
- Updated: 2026-09-14T17:17:07.000Z
- Author: David McFarland
- Tags: FDA Policy/General, #legacy-id-D5150270

*Federal Register* notice: FDA is making available a draft guidance entitled *Studying Multiple Versions of a Cellular or Gene Therapy Product in an Early-Phase Clinical Trial*. The document addresses how sponsors can gather preliminary evidence of safety and activity using multiple versions of a cellular or gene therapy product in a single clinical trial. To view the notice, click [here](https://www.govinfo.gov/content/pkg/FR-2021-09-30/pdf/2021-21322.pdf?ref=fdaweb.com).