EMBARK Study Summary: Delandistrogene Moxeparvovec Gene Therapy in Duchenne Muscular Dystrophy

A phase 3 multinational clinical trial assessed the efficacy and safety of delandistrogene moxeparvovec, a gene therapy for Duchenne muscular dystrophy (DMD), in ambulatory boys aged 4–7 years. 125 participants were randomized to receive either a single intravenous dose of delandistrogene moxeparvovec or placebo.

• Primary Outcome: The key measure was change in North Star Ambulatory Assessment (NSAA) score at 52 weeks. No statistically significant difference was found between groups.

• Secondary Outcomes: Micro-dystrophin expression was substantially higher in treated patients; some functional tests (time to rise, stride velocity, time to ascend 4 steps) showed nominal improvement, but overall results were not statistically significant.

• Safety: The safety profile was manageable, with no new safety signals, deaths, or clinically significant complement-mediated events. Serious treatment-related adverse events occurred in 11.1% of treated patients.

Conclusion: While delandistrogene moxeparvovec did not show a significant improvement in functional ability at 52 weeks, some secondary measures and exploratory endpoints indicated potential disease stabilization. The safety findings were consistent with previous trials, supporting further research for gene therapy in DMD.