Scholar Rock publishes SAPPHIRE trial data in The Lancet

Scholar Rock (SRRK) announced that study results from the pivotal Phase 3 SAPPHIRE trial were published in the peer-reviewed journal The Lancet Neurology. The data showed that children and adults with SMA had improved motor function with apitegromab-as measured by the gold-standard Hammersmith Functional Motor Scale Expanded-and decreased motor function with placebo despite all participants receiving ongoing survival motor neuron-targeted treatment. The mean difference in change from baseline in HFMSE was 1.8 points for all patients receiving apitegromab 10 mg/kg and 20 mg/kg compared to placebo in the 2-12-year-old efficacy population. Patients receiving 20 mg/kg of apitegromab showed a 1.4 point mean difference compared to placebo. Analysis performed in the ages 2-21-year-old population showed clinically meaningful and consistent improvement in HFMSE with apitegromab across pre-specified subgroups and geographic region. For secondary endpoints measured on patients aged 2-12 receiving apitegromab or placebo, the following improvements were observed: 30.4% of patients receiving apitegromab had 3-point improvement in HFMSE versus 12.5% of patients on placebo at 52 weeks. 19.6% of patients receiving apitegromab had =4-point improvement in HFSME versus 6.3% of patients on placebo at 52 weeks. Positive trends were observed across other motor function outcome measures, including Revised Upper Limb Module and World Health Organization motor development milestones. The company submitted a biologics license application application for apitegromab to the FDA, which has been accepted under priority review with a target action date of September 22, under the Prescription Drug User Fee Act. Apitegromab is also under review by the European Medicines Agency. In anticipation of potential regulatory approvals, Scholar Rock is planning for a U.S. commercial launch of apitegromab for SMA in 2025, with European launch projected in 2026.