Stealth BioTherapeutics to Present Top-Line Data From MMPOWER-2 Phase 2 Continuation Trial at Mitochondrial Medicine Symposium 2017

MMPOWER-2 assessed once daily dosing, tolerability and efficacy of elamipretide in patients who completed the MMPOWER clinical trial

Company to feature presentation from primary mitochondrial myopathy program

BOSTON – June 15, 2017 – Stealth BioTherapeutics (Stealth), a clinical-stage biopharmaceutical company developing therapeutics to treat mitochondrial dysfunction, today announced the presentation from the Company’s primary mitochondrial myopathy (PMM) program will be featured at Mitochondrial Medicine Symposium 2017, the United Mitochondrial Disease Foundation (UMDF) symposium, from June 28 – July 1, 2017 in Washington D.C. The presentation will include top-line results from MMPOWER-2, a Phase 2 continuation trial evaluating the safety, tolerability and efficacy of treatment with elamipretide for PMM in patients with genetically confirmed mitochondrial disease previously treated in the MMPOWER study. Data from the MMPOWER-2 trial will be presented at the UMDF symposium on Thursday, June 29 at 8:00 a.m. EDT.

“People with PMM, for which there are no FDA-approved therapies, experience debilitating muscle weakness and severe fatigue that can make even simple daily tasks challenging. We are focused on developing products designed to address this unmet medical need with our mitochondrial medicine platform,” said Stealth Chief Executive Officer Reenie McCarthy. “We look forward to discussing the progress of our clinical programs and the MMPOWER-2 data at the UMDF symposium. The findings, together with our learnings from the MMPOWER study, will be critical in informing our plans for a Phase 3 program in this patient population.”

For additional information on Stealth’s program in PMM or elamipretide, please refer to Stealth’s website.


MMPOWER-2 is a Phase 2, randomized, double-blind, placebo-controlled crossover study to evaluate the safety, tolerability and efficacy of four weeks’ treatment with once-daily subcutaneous (SC) injections of elamipretide or placebo in thirty patients with PMM previously treated in the MMPOWER study.

Subjects treated in the MMPOWER-2 study were randomized (1:1) to receive either four weeks of treatment with 40 mg elamipretide administered once daily SC in the first treatment period followed by four weeks of treatment with placebo administered once daily SC in the second treatment period, or vice versa. The two treatment periods were separated by a four-week washout period.

The primary efficacy endpoint is change in distance walked in six minutes at the end of each four-week treatment period. Secondary endpoints include safety and tolerability assessments, patient-reported outcomes and global impression scales.

About Stealth

We are a privately held clinical-stage biotechnology company focused on the development of therapeutics for diseases involving mitochondrial dysfunction. We believe there is a strong rationale for our lead product candidate, elamipretide, in indications in these diseases based on encouraging preclinical and early clinical data. We are investigating elamipretide in three primary mitochondrial diseases – primary mitochondrial myopathy (PMM), Barth syndrome and Leber’s hereditary optic neuropathy (LHON) – as well as in heart failure, Fuchs’ corneal dystrophy and dry age-related macular degeneration. We received Fast Track designation for elamipretide for the treatment of PMM from the FDA in December 2015. We are developing our second product candidate, SBT-20, for central nervous system disorders. Our mission is to be the leader in mitochondrial medicine. To learn more information about us and our pipeline, visit


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