A Gene Transfer Therapy Study to Evaluate the Safety and Efficacy of Delandistrogene Moxeparvovec (SRP-9001) in Participants With Duchenne Muscular Dystrophy (DMD)

A Phase 3 Multinational, Randomized, Double-Blind, Placebo-Controlled Systemic Gene Delivery Study to Evaluate the Safety and Efficacy of SRP-9001 in Subjects With Duchenne Muscular Dystrophy (EMBARK)

The study will evaluate the safety and efficacy of gene transfer therapy in boys with DMD. It is a randomized, double-blind, placebo-controlled study. The participants who are randomized to the placebo arm will have an opportunity for treatment with gene transfer therapy at the beginning of the second year.

Inclusion Criteria:

• Is ambulatory and from 4 to under 8 years of age at time of randomization.
• Definitive diagnosis of DMD based on documented clinical findings and prior genetic testing.
• Ability to cooperate with motor assessment testing.
• Stable daily dose of oral corticosteroids for at least 12 weeks prior to Screening, and the dose is expected to remain constant throughout the study (except for modifications to accommodate changes in weight).
• rAAVrh74 antibody titers are not elevated as per protocol-specified requirements.
• A pathogenic frameshift mutation or premature stop codon contained between exons 18 and 79 (inclusive), with the exception of mutation fully contained within exon 45.

Exclusion Criteria:

• Exposure to gene therapy, investigational medication, or any treatment designed to increase dystrophin expression within protocol specified time limits.
• Abnormality in protocol-specified diagnostic evaluations or laboratory tests.
• Presence of any other clinically significant illness, medical condition, or requirement for chronic drug treatment that in the opinion of the Investigator creates unnecessary risk for gene transfer.

Other inclusion or exclusion criteria could apply.