NS-050/NCNP-03 in Boys With DMD (Meteor50)

Inclusion Criteria:

• Male ≥ 4 years and <16 years of age;

• Confirmed DMD exon deletion in the dystrophin gene that is amenable to skipping ofexon 50 to restore the dystrophin mRNA reading frame;

• Able to walk independently without assistive devices;

• Able to complete the TTSTAND without assistance in <20 seconds;

• Stable dose of glucocorticoid for at least 3 months and the dose is expected toremain on a stable dose for the duration of the study.

Other inclusion criteria may apply.

Exclusion Criteria:

• Evidence of symptomatic cardiomyopathy;

• Current or previous treatment with anabolic steroids (e.g., oxendolone, oxandrolone)or products containing resveratrol or adenosine triphosphate within 3 months priorto first dose of study drug;

• Currently taking another investigational drug or has taken another investigationaldrug within 3 months prior to the first dose of study drug;

• Surgery within the 3 months prior to the first dose of study drug or planned duringthe study duration;

• Having taken any gene therapy.

Other exclusion criteria may apply.