> ## Content Index
> Fetch the complete content index at: https://www.fdaweb.com/llms.txt
> Use this file to discover other available public pages before exploring further.

# FDA Rejects Biogen's High-Dose Spinraza
- URL: https://www.fdaweb.com/fda-rejects-biogens-high-dose-spinraza/
- Published: 2025-09-23T12:00:00.000Z
- Updated: 2026-09-14T15:22:21.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5159923

FDA has issued Biogen a complete response letter on a supplemental NDA for a high-dose regimen of Spinraza (nusinersen) for treating spinal muscular atrophy (SMA). The letter requested an update to the technical information included in the Chemistry Manufacturing and Controls module of the submission, according to the company. Spinraza 12mg/5 mL injection is currently approved for treating infants, children and adults with SMA.