Viltolarsen in Japanese Duchenne muscular dystrophy patients: A phase 1/2 study.

Treatment with viltolarsen 40 or 80 mg/kg elicited an increasing trend in dystrophin expression and exon 53 skipping levels, and was safe and well tolerated. The decline in motor function appeared less marked in patients with higher dystrophin levels; this may warrant further investigation. This study supports the potential clinical benefit of viltolarsen.