This is an open-label, multi-center study to evaluate the efficacy and safety of eteplirsen in patients with genotypically confirmed Duchenne muscular dystrophy (DMD) with genetic deletions amenable to exon 51 skipping (treated group), with a concurrent control arm of DMD patients not amenable to exon 51 skipping (untreated group). Following primary efficacy endpoints, dosing will continue to week 144 to evaluate the long term effects of eteplirsen.~Patients in the treated group will receive once weekly intravenous (IV) infusions of 30 mg/kg Eteplirsen for 96 weeks, followed by a safety extension (not to exceed 48 weeks). Patients in the untreated group will not receive treatment.~Clinical efficacy will be assessed at regularly scheduled study visits, including functional tests such as the six minute walk test. Patients in the treated group will undergo a muscle biopsy at Baseline and a second muscle biopsy over the course of the study. Patients in the untreated group will not undergo muscle biopsy.~Safety, including adverse event monitoring and routine laboratory assessments, will be continuously monitored for all patients.
The main objective of this study is to provide evidence of efficacy of eteplirsen (AVI-4658) in Duchenne muscular dystrophy (DMD) patients that are amenable to skipping exon 51. Additional objectives include evaluation of safety, biomarkers and the long-term effects of eteplirsen up to 96 weeks, followed by a safety extension (not to exceed 48 weeks).