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

Sarepta Therapeutics

Status and phase: Active, not recruiting; Phase 3

Conditions: Duchenne Muscular Dystrophy

Treatments: Genetic: placebo; Genetic: delandistrogene moxeparvovec

Study type: Interventional

Funder types: Industry

Identifiers

NCT05881408

2020-002372-13 (EudraCT Number)

2024-512626-28-00 (Other Identifier)

SRP-9001-303

Details and patient eligibility

About

The study will evaluate the safety and efficacy of delandistrogene moxeparvovec gene transfer therapy in non-ambulatory and ambulatory males with DMD. This is a randomized, double-blind, placebo-controlled 2-part study. Participants will be in the study for approximately 128 weeks. All participants will have the opportunity to receive intravenous (IV) delandistrogene moxeparvovec in either Part 1 or Part 2.

Enrollment: 148 estimated patients

Sex: Male

Volunteers: No Healthy Volunteers

Inclusion criteria

• Definitive diagnosis of DMD based on documented clinical findings and prior genetic testing.
• Cohort 1 only: Non-ambulatory per protocol-specified criteria.
• Cohort 2 only: Ambulatory per protocol-specified criteria and ≥8 to <18 years of age at the time of Screening.
• 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).
• Recombinant Adeno-Associated Virus Serotype rh74 (rAAVrh74) antibody titers are not elevated as per protocol-specified requirements.
• A pathogenic frameshift mutation or premature stop codon in the DMD gene, except for any deletion mutations in exon 8 and/or 9.

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.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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148 participants in 2 patient groups, including a placebo group

Delandistrogene Moxeparvovec followed by Placebo

Experimental group

Description:

Participants will receive single IV infusion of delandistrogene moxeparvovec on Day 1. Then, participants will receive a single IV infusion of matching placebo at approximately 72 weeks.

Treatment:

Genetic: delandistrogene moxeparvovec

Genetic: placebo

Placebo followed by Delandistrogene Moxeparvovec

Placebo Comparator group

Description:

Participants will receive matching placebo IV infusion on Day 1. Then, participants will have the opportunity to receive a single IV infusion of delandistrogene moxeparvovec at approximately 72 weeks.

Treatment:

Genetic: delandistrogene moxeparvovec

Genetic: placebo