Scholar Rock announced that the U.S. Food and Drug Administration (FDA) has issued a Complete Response Letter (CRL) for its Biologics License Application for apitegromab, a potential treatment for spinal muscular atrophy (SMA). The CRL was issued solely due to manufacturing observations at Catalent Indiana LLC, a third-party fill-finish facility, and did not raise concerns about apitegromab’s safety or efficacy data. Scholar Rock plans to resubmit the application once Catalent’s remediation efforts are completed. Apitegromab, which has received multiple FDA designations including Orphan Drug and Fast Track, is the first muscle-targeted therapy candidate to show clinical success in SMA and remains under review by the European Medicines Agency, with a decision expected in mid-2026.