Ph2 Open-label Study of AOC 1044 in Duchenne Muscular Dystrophy Participants With Mutations Amenable to Exon44 Skipping

AOC 1044-CS2 (EXPLORE44-OLE) is an open label, extension study to Part B of AOC 1044-CS1 (EXPLORE44). AOC 1044-CS2 is designed to evaluate the long-term safety, tolerability, pharmacokinetics, and exploratory efficacy of AOC 1044.

All participants who enroll in AOC 1044-CS2 will receive active treatment. The treatment period is 2 years with IV dosing every 6 weeks.

Once participants have completed active treatment, they will be followed through a 3-month safety follow-up period. The sponsor may extend active treatment beyond 2 years at a future timepoint.

Key Inclusion Criteria

Rollover Participants:

• Satisfactorily completed AOC 1044-CS1 (EXPLORE44) as determined by the Investigator and Sponsor
• No significant tolerability issues with AOC 1044

De novo Participants:

• Aged 7 to 27 years, inclusive, at the time of informed consent
• Clinical diagnosis of DMD or clear onset of DMD symptoms at or before the age of 6 years
• Confirmation of DMD gene mutation amenable to exon 44 skipping
• Weight ≥ 23 kg
• Ambulatory or non-ambulatory

• Ambulatory participants: LVEF ≥50% and FVC≥50%
• Non-ambulatory participants: LVEF ≥45% and FVC≥40%
• PUL 2.0 entry item A ≥3
• If on corticosteroids, stable dose for 30 days before screening and throughout the study

Key Exclusion Criteria

Rollover Participants:

• Presence of any new condition or worsening of existing condition that could affect a participant's safety or ability to comply with study procedures

De novo Participants:

• Serum hemoglobin < lower limit of normal
• Uncontrolled hypertension or diabetes
• Prior treatment with any cell or gene therapy
• Prior treatment with another exon 44 skipping agent within 6 months prior to informed consent
• Recently treated with an investigational drug
• History of multiple drug allergies