Long-Term Outcomes of Ataluren in Duchenne Muscular Dystrophy

Inclusion Criteria: * Male sex * Age ≥5 years * Phenotypic evidence of Duchenne Muscular Dystrophy * Nonsense point mutation in the dystrophin gene * Use of systemic corticosteroids (prednisone/prednisolone or deflazacort)for a minimum of 12 months immediately prior to start of study treatment, with no significant change in dosage or dosing regimen for a minimum of 3 months immediately prior to start of study treatment * 6MWD ≥150 meters * Ability to perform timed function tests within 30 seconds * Willingness and ability to comply with scheduled visits, drug administration plan, study procedures, laboratory tests, and study restrictions. Exclusion Criteria: * Any change in prophylaxis treatment for cardiomyopathy within 1 month prior to start of study treatment. * Ongoing intravenous (IV) aminoglycoside or IV vancomycin therapy. * Prior or ongoing therapy with ataluren. * Known hypersensitivity to any of the ingredients or excipients of the study drug * Exposure to another investigational drug within 6 months prior to start of study treatment, or ongoing participation in any interventional clinical trial. * History of major surgical procedure within 12 weeks prior to start of study treatment, or expectation of major surgical procedure during the 72-week placebo-controlled treatment period. * Requirement for daytime ventilator assistance or any use of invasive mechanical ventilation via tracheostomy. * Uncontrolled clinical symptoms and signs of congestive heart failure * Elevated serum creatinine or cystatin C at screening.