Scholar Rock Holding Corp

Scholar Rock is a global biopharmaceutical company focused on improving the lives of children and adults with spinal muscular atrophy (SMA) and other rare, severe, and debilitating neuromuscular diseases. The company specializes in the biology of the transforming growth factor beta (TGFβ) superfamily, using its understanding of molecular mechanisms of growth factor activation to develop a proprietary platform. This platform enables the discovery and development of monoclonal antibodies that target the precursor, or latent, forms of growth factors locally and selectively. Based on this technology, Scholar Rock is developing an anti-myostatin pipeline. Its lead product candidates include apitegromab, a subcutaneous formulation of apitegromab, and SRK-439. Apitegromab is an investigational, fully human monoclonal antibody that inhibits myostatin activation by selectively binding to the pro- and latent forms of myostatin in skeletal muscle. Myostatin negatively regulates muscle mass, so its inhibition increases muscle mass and strength. Apitegromab is being developed for the treatment of people with SMA and facioscapulohumeral muscular dystrophy (FSHD). In October 2024, positive data were reported from the Phase 3 SAPPHIRE study of apitegromab in children and adults with SMA. Regulatory approvals in the U.S. and Europe are anticipated in 2026. A Phase 2 study evaluating apitegromab in patients with FSHD is expected to begin in mid-2026. Beyond the current intravenous (IV) formulation, a subcutaneous (SC) formulation of apitegromab is also in development. A Phase 1 study in healthy volunteers demonstrated that SC apitegromab has favorable bioavailability and a comparable pharmacodynamic profile to IV administered apitegromab.