Safety and Efficacy Study of IGF-1 in Duchenne Muscular Dystrophy

Inclusion Criteria: * DMD diagnosed with mutational testing and/or complete absence of dystrophin on muscle biopsy * Proximal pelvic girdle weakness (Gower's maneuver, difficulty with arising from floor and going up steps) * Male * Age \> 5 years of age * Bone maturation (assess by bone age x-ray): \</= 11 years of age * Daily GC (prednisone or deflazacort) therapy for \> 12 months * Ambulatory * Informed consent * Willingness and ability to comply with all protocol requirements and procedures Exclusion Criteria: * Current or prior treatment with growth hormone or IGF-1 therapy * Non-ambulatory * Pubertal (based on clinical Tanner staging examination) * Congestive cardiac failure * History of intracranial hypertension * Daytime ventilatory dependence (non-invasive or tracheostomy) * Concomitant therapy - any other medications/supplements that would be considered, in the opinion of the investigators, to affect muscle function, need to have been started 3 months prior to enrollment * Patients enrolled in other clinical drug trials * Any physical or mental conditions which may, in the investigators'opinions, render the subject unable to complete the tasks of the study appropriately * There will be no selection by ethnicity