Therapeutic Trial of EPI -743 In Patients With Disorders of Energy Utilization or Oxidation-Reduction

The clinical manifestations of disorders of energy metabolism and defects in oxidation/reduction are similar because the basic defect involves the inability to transfer electrons. The same is true for many mitochondrial diseases. Affected patients exhibit a wide variety of signs and symptoms, but the most frequent and earliest dysfunctions occur in the muscle and brain, where energy requirements are high. The diagnosis of this type of defect is problematic because of the nonspecific and protean clinical manifestations of these disorders. Treatment is equally challenging, since the exact locus of the primary defect generally remains enigmatic. As a consequence, physicians rely upon generic cocktails of vitamin co-factors or endogenous intermediates intended to enhance mitochondrial electron transport, diminish the damage of reactive oxygen species, and promote energy production. The field is such a morass that, in general, it calls for trial-and-error treatment based upon empiric data. Edison Pharmaceuticals, Inc, has developed an in vitro assay that utilizes patient fibroblasts to model the innate susceptibility to oxidative stress caused by the disorders of energy metabolism and oxidation/reduction. The assay system also determines if the cells respond with increased viability to an IND drug called EPI-743. We propose a clinical trial that enrolls 20 children who meet three criteria. First, they must have a disorder that, based upon studies performed in a clinical protocol such as 76-HG-0238 ("Diagnosis and Treatment of Patients with Inborn Errors of Metabolism and Other Genetic Disorders"), is consistent with a defect in energy metabolism or oxidation/reduction. Second, their cultured fibroblasts must exhibit a defect in the ability to withstand oxidant stress. Third, their fibroblasts must respond to EPI-743 in vitro by showing improved viability under conditions of oxidative stress. This protocol is a double-blind, placebo-controlled crossover study with 6-month periods of treatment and a two-month washout period. Patients will be admitted to the NIH Clinical Center for 2-5 days every 3 months. The primary outcome measure will be quality of life based upon the Newcastle Paediatric Mitochondrial Disease Scale (NPMDS) for ages 2-11 years; parts IIII

will be evaluated separately from part IV. Secondary outcome measures will be tailored to each patient's laboratory, imaging, and clinical abnormalities. Results while receiving EPI-743 will be compared to results while receiving placebo; both repeated measures analyses and Student's t test will be employed.