A Gene Transfer Therapy Study to Evaluate the Safety and Efficacy of Delandistrogene Moxeparvovec (SRP-9001) Following Imlifidase Infusion in Participants With Duchenne Muscular Dystrophy (DMD) Determined to Have Pre-existing Antibodies to Recombinant Adeno-Associated Virus Serotype (rAAVrh74)

Sarepta Therapeutics

Status and phase: Invitation-only; Phase 1

Conditions: Duchenne Muscular Dystrophy

Treatments: Biological: imlifidase; Genetic: delandistrogene moxeparvovec

Study type: Interventional

Funder types: Industry

Identifiers

NCT06241950

2022-003407-15 (EudraCT Number)

SRP-9001-104

Details and patient eligibility

About

This is a gene transfer therapy study evaluating the safety of delandistrogene moxeparvovec and delandistrogene moxeparvovec dystrophin expression in association with imlifidase, in participants with DMD with pre-existing antibodies to rAAVrh74 over a period of 104 weeks.

Enrollment: 6 estimated patients

Sex: Male

Ages: 4 to 9 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Ambulatory per protocol specified criteria.
• Has a definitive diagnosis of DMD prior to Screening based on documentation of clinical findings and confirmatory genetic testing.
• Ability to cooperate with motor assessment testing.
• Has elevated rAAVrh74 antibody titers per protocol-specified requirements.
• A pathogenic frameshift mutation, nonsense mutation or premature stop codon or pathogenic variant in the DMD gene that is expected to lead to absence of dystrophin protein.
• 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).

Exclusion criteria

• Previous treatment with imlifidase.
• Presence of any other clinically significant illness, including cardiac, pulmonary, hepatic, renal, hematologic, immunologic, or behavioral disease, or infection or malignancy or concomitant illness or requirement for chronic drug treatment that in the opinion of the Investigator creates unnecessary risks for receiving the study drugs or a medical condition or extenuating circumstance that, in the opinion of the Investigator, might compromise the participant's ability to comply with the protocol required testing or procedures or compromise the participant's wellbeing, safety, or clinical interpretability.
• Exposure to gene therapy, investigational medication, or other protocol-specified treatment within the protocol specified time limits.
• Abnormality in protocol-specified diagnostic evaluations or laboratory tests.

Note: Other inclusion or exclusion criteria could apply.

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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6 participants in 1 patient group

Delandistrogene Moxeparvovec after Imlifidase Infusion

Experimental group

Description:

Participants may receive 1 or 2 doses of imlifidase, depending on rAAVrh74 antibody titer results. Then, based on their rAAVrh74 antibody titer, eligible participants may receive 1 dose of delandistrogene moxeparvovec infusion.

Treatment:

Genetic: delandistrogene moxeparvovec

Biological: imlifidase