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# Proposed Rule on Biologic Master Files
- URL: https://www.fdaweb.com/proposed-rule-on-biologic-master-files/
- Published: 2019-06-28T12:00:00.000Z
- Updated: 2026-09-15T01:35:43.000Z
- Author: David McFarland
- Tags: FDA Policy/General, #legacy-id-D5144450

*Federal Register* proposed rule: FDA has proposed to amend its regulations concerning the use of master files for biological products. If finalized, the rule would allow certain biological products to continue to incorporate by reference information about drug substances, drug substance intermediates, or drug products contained in master files. The proposed rule also would codify FDA’s practice of permitting applications for biological products submitted under the PHS Act to incorporate by reference information other than drug substance, drug substance intermediate, or drug product information contained in a master file. To view the notice, click [here](https://www.govinfo.gov/content/pkg/FR-2019-06-28/pdf/2019-13753.pdf?ref=fdaweb.com).