Clinical Research Directory

Inclusion Criteria: * Genetically confirmed FSHD1 based on Screening evaluation or source verifiable medical record * Clinical severity score between 3 and 8 (scale, 0 to 10) * Must have eligible lower extremity muscle for biopsy as determined from MRI by a central reader * A 12-lead electrocardiogram (ECG) at Screening with no abnormalities that may compromise participant's safety in the study * Participants of childbearing potential and their partners must use highly effective contraception during the study and for at least 12 weeks following the end of study or last dose of study medication, whichever is later. Males must not donate sperm during the study from Day 1 until at least 12 weeks following the end of study or last dose of study medication, whichever is later. Exclusion Criteria: * Human Immunodeficiency Virus (HIV) infection as shown by presence of anti-HIV antibody (seropositive) at Screening * Seropositive for hepatitis B (HBV) or hepatitis C (HCV) at Screening * Uncontrolled hypertension * Severe cardiovascular disease * History of thrombolic events * Platelet count less that the lower limit of normal at Screening * History or presence of: a hypercoagulable state, nephrotic range proteinuria, antiphospholipid antibody syndrome, myeloproliferative disease, inability to ambulate, use of hormone-based contraceptives. * Any contraindication to muscle biopsy or MRI Note: additional inclusion/exclusion criteria may apply per protocol