Capricor shares crater more than 67% after FDA questions Deramiocel trial

Capricor Therapeutics shares plunged more than 67% on Monday, the stock's steepest one-day drop on record, after U.S. Food and Drug Administration (FDA, U.S. drug regulator) briefing documents challenged the effectiveness of Deramiocel, the company's experimental cell therapy for Duchenne muscular dystrophy. The sell-off followed the release of materials for a July 29 meeting of the FDA's Cellular, Tissue, and Gene Therapies Advisory Committee, where advisers will review Capricor's Biologics License Application (BLA, formal request to market a biologic drug). FDA reviewers said the Phase 3 Hope-3 trial failed to show a statistically significant benefit over placebo and missed its pre-specified primary and secondary efficacy endpoints after 12 months. The agency also highlighted post-study changes to the statistical analysis plan, including revisions to endpoints, analytical methods and missing-data handling, and said the final plan was not submitted before the BLA filing. That directly conflicts with Capricor's December 2025 claim that the study met both its primary endpoint on upper-limb function and key secondary endpoint on cardiac function. Because Deramiocel's approval bid relies on a single pivotal trial, the FDA's assessment raises doubts about whether the application meets the substantial evidence of effectiveness standard. A final FDA decision is due by the Prescription Drug User Fee Act (PDUFA, drug review deadline) date of August 22, 2026, and investors are now bracing for the possibility of a complete response letter requiring additional clinical trials.