High Dose Regimen of Nusinersen Receives Positive CHMP Opinion for the Treatment of Spinal Muscular Atrophy

Core Viewpoint - Biogen Inc. announced a positive opinion from the CHMP of the EMA recommending the approval of a high dose regimen of nusinersen for treating 5q spinal muscular atrophy (SMA), with a final decision expected in January 2026 [1][7]. Company Developments - The high dose regimen of nusinersen includes a loading dose of two 50 mg doses 14 days apart, followed by a maintenance dose of 28 mg every four months for treatment-naïve patients [3][10]. - Nusinersen, marketed as SPINRAZA, is currently approved in over 71 countries at a lower dose of 12 mg [2][13]. - The high dose regimen has shown promising results in clinical studies, with significant improvements in motor function and a reduction in the risk of death or permanent ventilation [4][5]. Clinical Study Insights - The positive CHMP opinion is based on data from the Phase 2/3 DEVOTE study, which evaluated the efficacy and safety of the high dose regimen in both treatment-naïve and previously treated patients [3][11]. - In the pivotal Part B cohort of the DEVOTE study, treatment-naïve infants showed a statistically significant improvement in motor function compared to a matched sham group, with a mean difference of 26.19 points [4][11]. - The high dose regimen was generally well tolerated, with adverse events consistent with SMA and no new safety concerns identified [6][10]. Regulatory Landscape - The high dose regimen is under review by the U.S. FDA, with a decision expected by April 3, 2026 [9]. - Biogen is actively working with regulatory authorities worldwide to advance the high dose regimen as an additional option for SMA patients [9].