Jerry Mendell of Ohio State University and colleagues from seven countries reported the failure of a phase III clinical trial of gene therapy for Duchenne muscular dystrophy. The multicenter, randomized EMBARK trial involved 124 children aged 4 to 7 years with this diagnosis. Approximately half received a single placebo injection, while the other half received the delanistrogene moxeparvovec at a dose of 1.33 × 10 vector genomes per kilogram of body weight. This drug is a working copy of the dystrophin gene, which is associated with the disease, on the adeno-associated viral vector rh74. The results of the study were published in the journal Nature Medicine.
After 52 weeks, the mean change in NSAA symptom scores in the intervention and control groups (primary endpoint) was 2.57 versus 1.92 points; a difference of 0.65 points (95% confidence interval, -0.45 to 1.74; p = 0.2441)—not statistically significant. The results for individual motor skills (secondary endpoints) were also nonsignificant. The authors of the study do not rule out the possibility that this is due to the relatively short trial period. Patient monitoring continues, as with other ongoing trials of the drug.
