An Extension Study to Assess Vamorolone in Boys With Duchenne Muscular Dystrophy (DMD)

Inclusion Criteria

• Participant's parent or legal guardian has provided written informed consent/HIPAA authorization prior to any extension study-specific procedures;
• Participant has previously completed study VBP15-002 up to and including the Week 4 Follow-up assessments within 8 weeks prior to enrollment; and
• Participant and parent/guardian are willing and able to comply with scheduled visits, study drug administration plan, and study procedures.

Exclusion Criteria

• Participant had a serious or severe adverse event in study VBP15-002 that, in the opinion of the Investigator, was probably or definitely related to vamorolone use and precludes safe use of vamorolone for the subject in this study;
• Participant has current or history of major renal or hepatic impairment, diabetes mellitus or immunosuppression;
• Participant has current or history of chronic systemic fungal or viral infections;
• Participant has used mineralocorticoid receptor agents, such as spironolactone, eplerenone, canrenone (canrenoate potassium), prorenone (prorenoate potassium), mexrenone (mexrenoate potassium) within 4 weeks prior to the first dose of study medication;
• Participant has evidence of symptomatic cardiomyopathy. [Note: Asymptomatic cardiac abnormality on investigation would not be exclusionary];
• Participant is currently being treated or has received previous treatment with oral glucocorticoids or other immunosuppressive agents. [Notes: Past transient use of oral glucocorticoids or other oral immunosuppressive agents for no longer than 3 months cumulative, with last use at least 3 months prior to first dose of study medication, will be considered for eligibility on a case-by-case basis. Inhaled and/or topical corticosteroids prescribed for an indication other than DMD are permitted but must be administered at stable dose for at least 3 months prior to study drug administration];
• Subject has used idebenone within 4 weeks prior to the first dose of study medication;
• Participant has an allergy or hypersensitivity to the study medication or to any of its constituents;
• Participant has severe behavioral or cognitive problems that preclude participation in the study, in the opinion of the Investigator;
• Participant has previous or ongoing medical condition, medical history, physical findings or laboratory abnormalities that could affect safety, make it unlikely that treatment and follow-up will be correctly completed or impair the assessment of study results, in the opinion of the Investigator; or
• Participant is currently taking any investigational drug, or has taken any investigational drug other than vamorolone within 3 months prior to the start of study treatment.

Note: Participants may be re-evaluated if ineligible due to a transient condition which would prevent the subject from participating