Safety Study of Eteplirsen to Treat Advanced Stage Duchenne Muscular Dystrophy

Inclusion Criteria: * Male 7 - 21 years of age * Diagnosis of DMD with a mutation that is amenable to exon 51 skipping, confirmed by a genetic report * Stable dose of oral corticosteroids for at least 24 weeks or has not received corticosteroids for at least 24 weeks * Non-ambulatory, or incapable of walking ≥300 meters on the 6-Minute Walk Test (6MWT). * Score of ≤4 on the Brooke Score for Arms and Shoulders. * Stable cardiac and pulmonary function * Use of contraceptives for sexually active males throughout the study * Willing to provide consent and comply with the study Exclusion Criteria: * Use of any pharmacologic treatment (other than corticosteroids) within 12 weeks that may have an effect on muscle strength or function (e.g., growth hormone, anabolic steroids). * Previous treatment with SMT C1100/BMN 195 at any time. * Previous treatment with drisapersen (PRO051) within the last 6 months. * Participation in any other DMD interventional clinical study within 12 weeks * Major change in physiotherapy regimen within the past 3 months * Major surgery within 3 months * Presence of other clinically significant illness * Use of an aminoglycoside antibiotic within 12 weeks or the need for this antibiotic or statin during study * Forced vital capacity % predicted \[FVC % predicted\] \<40%, or requiring daytime ventilation. * Require antiarrhythmic and/or antidiuretic therapy for heart failure. * Have a left ventricular ejection fraction (LVEF) of \<40%. * Prior or ongoing medical condition that could adversely affect the safety of the patient, make it unlikely that the course of treatment would be completed, or impair the assessment of study results.