Deramiocel Slows Upper Limb Decline in Duchenne Muscular Dystrophy; FDA Review Ongoing
Phase III data show deramiocel slowed upper limb decline by 54% in Duchenne muscular dystrophy. The FDA is re-evaluating the BLA with HOPE-3 results, with a submission of the clinical study report expected in February 2026.
The investigational cell therapy deramiocel slowed upper limb functional decline in boys and young men with Duchenne muscular dystrophy, according to data from the phase III HOPE-3 trial presented at the American Academy of Neurology annual meeting. At 12 months, the mean percent change from baseline in Performance of Upper Limb 2.0 (PUL 2.0) total score was −3.86 in the deramiocel group and −8.41 in the placebo group, a difference of 4.55 (P=0.029), representing a 54% slowing of disease progression in one year.
Secondary endpoints also showed benefit. Mid-level PUL 2.0 scores indicated a 65% slowing of progression (P=0.008). The Duchenne Video Assessment "Eat 10 Bites" score at 12 months showed that deramiocel reduced decline in independent feeding by 83%. Deramiocel also preserved left ventricular ejection fraction (LVEF) with a treatment difference of 2.4% (P=0.041) and slowed late gadolinium enhancement (LGE), a measure of cardiac fibrosis, by −3.0 segments (P=0.022). The therapy was safe and well tolerated, with mild-to-moderate flu-like symptoms that were transient and resolved within 24 to 48 hours after infusion. One serious adverse event occurred in the deramiocel group (1.9%) and five occurred in the placebo group (9.6%).
The phase III HOPE-3 trial was a double-blind study that randomized 106 Duchenne patients at least 10 years old to quarterly infusions of deramiocel (54 participants) or placebo (52 participants). Participants had a mean age of 15 years; most (84.9%) were non-ambulatory, and 24.5% were receiving exon-skipping therapy. All patients were on background stable corticosteroid therapy.
Deramiocel is a novel cellular therapy consisting of allogeneic cardiosphere-derived cells that have been shown to confer immunomodulatory and anti-fibrotic properties. It previously demonstrated benefit on skeletal muscle function in the HOPE-2 phase II study and its open-label extension.
In July 2025, the FDA rejected a biologics license application from Capricor Therapeutics, citing insufficient clinical evidence from the HOPE-2 trial and requesting additional data. The agency is now re-evaluating the application with results from HOPE-3. In January 2026, Capricor announced that the FDA formally requested the complete clinical study report and supporting data from HOPE-3. Preparation of the report is underway and the requested materials are expected to be submitted in February 2026. The company anticipates that this submission may lead to the assignment of a new PDUFA action date.
Duchenne muscular dystrophy is caused by mutations in the DMD gene. Loss of the protein dystrophin triggers progressive degeneration of skeletal and cardiac muscle, a pro-inflammatory and pro-fibrotic immune response, and a steady decline in function that can culminate in life-threatening cardiac events. The condition primarily affects males, with around 1 in 5,000 boys currently living with DMD.