An open-label, phase 1/2a, nonrandomized controlled clinical trial (NCT03375164) enrolled four DMD ambulatory males with a mean age of 5.1 years.86Patients received a single IV infusion (2.0 × 1014 vg/kg) of delandistrogene moxeparvovec and steroids.86At 12 weeks, immunohistochemistry of gastrocnemius muscle specimens revealed robust transgene expression in all patients, with a mean of 81.2% of muscle fibers expressing micro-dystrophin with a mean intensity of 96% at the sarcolemma. Here, DMD is linked to Duchenne muscular dystrophy.