Scholar Rock’s Stock Skyrockets 300% Following Successful Phase III Trial of Apitegromab for Spinal Muscular Atrophy

Successful Phase III Trial:
Scholar Rock's apitegromab, a monoclonal antibody targeting myostatin, demonstrated statistically significant and clinically meaningful improvement in motor function in patients with spinal muscular atrophy (SMA) in the Phase III SAPPHIRE trial.

Stock Performance:
The company's stock price soared by 300% following the announcement of the positive trial results, from $7.42 to $34.28.

Regulatory Plans:
Scholar Rock plans to file a Biologics License Application (BLA) to the US FDA and a marketing authorisation application (MAA) to the European Union in Q1 2025.

Clinical Outcomes:
Patients aged 2-12 treated with apitegromab showed a 1.8-point improvement in the Hammersmith Functional Motor Scale Expanded (HFMSE) compared to placebo, with 30% of apitegromab-treated patients achieving at least a 3-point improvement versus 12.5% of placebo comparators.

Funding:
Following the positive trial results, Scholar Rock raised $300 million from a stock offering to support regulatory submissions and launch preparation for apitegromab.

Unique Approach:
Apitegromab is the first muscle-targeted treatment candidate to demonstrate clinical proof-of-concept in SMA, offering a complementary approach to existing therapies by directly addressing muscle atrophy.