Safety, Tolerability, Efficacy of MTP-131 for Treatment of Mitochondrial Disease in Subjects From the MMPOWER Study

This randomized, double-blind, placebo-controlled, crossover study screened 32 subjects with primary mitochondrial myopathy (PMM) who had completed participation in the SPIMM-201 study where they had received 5 days of intravenous (IV) elamipretide (0.01, 0.10, or 0.25 mg/kg/hour infused for 2 hours) or placebo (randomized 3:1). The primary objective was to evaluate the effect of single daily subcutaneous (SC) doses of elamipretide administered for 4 weeks on the 6-minute walking distance (6MWD). Subjects were randomized (1:1) to one of two sequence groups: 4-weeks of treatment with 40 mg elamipretide administered once daily SC in Treatment Period 1 followed by 4-weeks of treatment with placebo administered once daily SC in Treatment Period 2 (separated by a 4-week washout period), or vice versa. Each sequence group went through 5 distinct periods: Screening, Treatment Period 1, Washout, Treatment Period 2, and Follow-Up. Safety, tolerability, pharmacokinetics (PK), and efficacy of subcutaneous elamipretide in this patient population were analyzed.