01 Aug, 2026
Duchenne muscular dystrophy (DMD) is an X-linked recessive neuromuscular disorder caused by pathogenic variants in the DMD gene, resulting in an absence or severe deficiency of dystrophin. Progressive degeneration of skeletal and cardiac muscle leads to loss of ambulation, respiratory insufficiency, dilated cardiomyopathy, and premature mortality. Although corticosteroids and mutation-specific therapies have improved outcomes in selected patients, treatment options for individuals with advanced disease remain limited.1-3
Deramiocel is an investigational allogeneic cardiosphere-derived cell (CDC) therapy developed to target the downstream inflammatory and fibrotic processes that drive disease progression in DMD rather than correcting the underlying genetic defect. CDCs exert immunomodulatory, anti-inflammatory, and anti-fibrotic effects through paracrine signaling, including the release of extracellular vesicles and microRNAs that influence tissue repair and fibrosis. This mutation-independent mechanism suggests that deramiocel may be applicable across all DMD genotypes.4-6
The Phase III HOPE-3 trial, a multicentre, randomized, double-blind, placebo-controlled study, evaluated intravenous deramiocel in 106 boys and young men (10–22 years) with advanced DMD. Participants received deramiocel or placebo every three months over a 12-month period. Treatment significantly slowed deterioration in upper-limb function, with an approximately 54% reduction in the rate of overall arm function decline and a 65% reduction in elbow function deterioration compared with placebo. These findings are clinically important because preservation of upper-extremity function is closely associated with maintaining independence and quality of life in non-ambulatory patients.7
Although no statistically significant improvement in global left ventricular systolic function was observed in the overall study population, subgroup analyses demonstrated better preservation of cardiac function among participants with established cardiomyopathy. In addition, serial cardiac magnetic resonance imaging suggested slower progression of myocardial fibrosis in treated patients, supporting the proposed anti-fibrotic mechanism of deramiocel. Nevertheless, these cardiac findings remain exploratory and require confirmation through larger studies with longer follow-up.7
The treatment demonstrated a favourable safety profile. No deaths occurred during the study, and most treatment-emergent adverse events were mild to moderate. Infusion-related hypersensitivity reactions occurred more frequently with deramiocel than placebo but generally resolved within 24–48 hours without long-term sequelae. Common adverse events included headache, pyrexia, nausea, cough, and transient tachycardia.7
The encouraging HOPE-3 findings build upon earlier evidence from the Phase II HOPE-2 trial, which also demonstrated slower deterioration in upper-limb performance following repeated intravenous administration of cardiosphere-derived cells in late-stage DMD. Together, these studies suggest that deramiocel may represent a promising disease-modifying therapy for advanced DMD by attenuating inflammation and fibrosis rather than restoring dystrophin expression. However, longer-term studies are required to establish the durability of clinical benefit, confirm its effects on cardiac outcomes, and determine whether treatment ultimately improves survival and quality of life.8,9
References:
1- Duchenne Muscular Dystrophy. Diagnosis and management of Duchenne muscular dystrophy, part 1: diagnosis and neuromuscular, rehabilitation, endocrine, and gastrointestinal and nutritional management. Lancet Neurol. 2018;17:251–267.
2- Duchenne Muscular Dystrophy. Diagnosis and management of Duchenne muscular dystrophy, part 2: respiratory, cardiac, bone health, and orthopaedic management. Lancet Neurol. 2018;17:347–361.
3- Parent Project Muscular Dystrophy. Current standards of care for Duchenne muscular dystrophy.
4- McDonald CM, et al. Repeated intravenous cardiosphere-derived cell therapy in late-stage Duchenne muscular dystrophy (HOPE-2): a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial. Lancet. 2022;399:1049–1058.
5- Lempriere S. Treatment with cardiosphere-derived cells could slow progression of Duchenne muscular dystrophy.Nat Rev Neurol. 2022;18:251.
6- Cell therapy for Duchenne muscular dystrophy: promises, challenges, and controversies. Stem Cell Reviews and Reports. 2025.
7- HOPE-3 Investigators. Deramiocel heart-derived cellular therapy in advanced Duchenne muscular dystrophy (HOPE-3): a phase 3, randomised, double-blind, placebo-controlled trial. Lancet. 2026. doi:10.1016/S0140-6736(26)01385-1.
8- A Novel In Vitro Potency Assay Demonstrating the Anti-Fibrotic Mechanism of Action of CDCs in Deramiocel.Cells. 2025.
9- ClinicalTrials.gov: HOPE-3 (NCT05126758).