Spironolactone Versus Prednisolone in DMD

Until recently, the only treatment shown to improve strength and preserve ambulation in DMD patients was the use of glucocorticoids, which are accompanied by significant side effects including obesity, cushingoid features, osteoporosis, and behavioral disturbances. Spironolactone is an aldosterone antagonist primarily used as a potassium sparing diuretic that is widely used in the pediatric population, with limited side-effects including gynecomastia and hyperkalemia. Recent studies by Dr. Rafael-Fortney have evaluated the effect of spironolactone treatment in several different mouse models of DMD. Her results show that treatment of these mice demonstrates increased muscle membrane stabilization while reducing the negative side-effects typically associated with standard of care glucocorticoids. This pilot study is designed to determine whether this commonly used medication, spironolactone, may have similar beneficial effects with a lower side effect profile and be applicable to a wider population of DMD patients. The hypothesis for this controlled pilot trial is that spironolactone and prednisolone are of equal efficacy in improving skeletal muscle function over a 6-month period, and that spironolactone will be well tolerated in this patient population. One outcome is that both drugs demonstrate equal efficacy in motor function. This would then serve as pilot data for a longer term study.