The primary objective of this study is to evaluate acute liver injury (ALI) rates associated with ELEVIDYS with the addition of sirolimus as an adjunct prophylactic immunosuppression agent.
Cohort 1 only: Is male at birth, ambulatory, and ≥ 4 years of age at the time of dosing.
Cohort 1 only: Is eligible for commercial ELEVIDYS.
Cohort 2 only: Is male at birth and has previously received ELEVIDYS in a commercial setting after pre-treatment with sirolimus and corticosteroids.
Cohort 1 only: Participants who are sexually active must agree to use, for the entire duration of the study, a condom and the female sexual partner must also use a medically acceptable form of birth control (eg, oral contraceptive).
Cohort 1 only: Contraindicated to receive ELEVIDYS per the United States Package Insert (USPI).
Cohort 1 only: Has serological evidence of current, chronic, or active human immunodeficiency virus, hepatitis C, or hepatitis B infection.
The participant's ability to comply with the protocol-required procedures, and/or
The participant's well-being or safety, and/or