Scholar Rock stock surges on positive spinal muscular atrophy treatment data

Investing.com — Shares of Scholar Rock Holdings skyrocketed 320% on Monday following the announcement of positive results from its Phase 3 SAPPHIRE clinical trial for apitegromab, a treatment for spinal muscular atrophy (SMA).

The trial met its primary endpoint, showing statistically significant improvements in motor function as measured by the Hammersmith Functional Motor Scale Expanded (HFMSE).

Scholar Rock explained in its press release that 30.4% of patients receiving apitegromab experienced a greater than three-point improvement compared to only 12.5% of those on a placebo.

Dr. Jay Backstrom, President and CEO of Scholar Rock, expressed enthusiasm for the results, stating, “The results clearly demonstrate robust and clinically meaningful improvement in motor function in patients with SMA.”

The company plans to submit a U.S. Biologics License Application and European Union marketing authorization application in the first quarter of 2025.

The company added that was no new safety findings were observed in the SAPPHIRE clinical trial and the profile was consistent with that observed in the Phase 2 TOPAZ clinical trial.

Following the news, Truist analysts said in a note that the study showed a clinically meaningful improvement of 1.8 points compared to placebo, reinforcing the unmet need for effective SMA treatments.

They reiterated a Buy rating for Scholar Rock and increased the price target from $20 to $36 per share.

“We see this as a validation of the company’s TGFbeta platform and of their strategy to evaluate anti-myostatin (a drug that improves muscle) on top of a drug that targets the genetic cause of the disease,” said Truist.

“We also see these data as a positive read-through to the company’s obesity program with readout in 2Q2025,” they added. As a reminder, while apitegromab is being evaluated in a Ph2 trial, company plans to develop SRK-439, a next gen anti-myostatin drug that has been engineered specifically for CVD in obesity.”