An Open-label Extension Study To Evaluate Safety Of PF-06252616 In Boys With Duchenne Muscular Dystrophy

This study is an open-label extension to protocol B5161002 and will provide an assessment of the long term safety, efficacy, pharmacodynamics and pharmacokinetics of intravenous dosing of PF 06252616 in boys with Duchenne muscular dystrophy. Approximately 105 eligible subjects will be assigned to receive a monthly individualized maximum tolerated dose based on their tolerability profile/data from B5161002. This study will not contain a placebo comparator. Subjects will undergo safety evaluations (Laboratory, cardiac monitoring, physical exams, x-ray, MRI), functional capacity evaluations (4 stair climb, range of motion, strength testing, Northstar Ambulatory Assessment, upper limb functional testing, six minute walk test and pulmonary function tests) and pharmacokinetic testing.