Capricor Therapeutics received a Complete Response Letter (CRL) from the FDA regarding its deramiocel cell therapy for cardiomyopathy in Duchenne muscular dystrophy (DMD). The agency cited insufficient evidence of effectiveness and requested additional clinical data. This marks a departure from prior regulatory flexibility in cell and gene therapies. Capricor plans to rely on ongoing Phase III data for future submissions. The company’s stock dropped significantly following the announcement.