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# FDA Extends Review on Sanofi Multiple Sclerosis NDA
- URL: https://www.fdaweb.com/fda-extends-review-on-sanofi-multiple-sclerosis-nda/
- Published: 2025-09-22T12:00:00.000Z
- Updated: 2026-09-14T15:22:19.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5159907

FDA has extended by three months its review of Sanofi’s multiple sclerosis drug tolebrutinib in response to additional analyses submitted during the ongoing NDA review. The agency determined that the new data constituted a “major amendment,” triggering the extension. The revised user fee review action target date is 12/28.

Tolebrutinib is described by the company as an oral and brain-penetrant Bruton's tyrosine kinase (BTK) inhibitor being evaluated for treating non-relapsing, secondary progressive multiple sclerosis (nrSPMS) and to slow disability accumulation independent of relapses in adults. The drug previously was granted a breakthrough therapy designation in nrSPMS, the first BTK inhibitor with that status, Sanofi says.