Stealth BioTherapeutics Initiates Phase 2 Study of Elamipretide in Patients Hospitalized with Congestive Heart Failure

Top-line results anticipated in second half of 2017

BOSTON – October 25, 2016 – Stealth BioTherapeutics (Stealth), a clinical-stage biopharmaceutical company developing investigational drugs to treat mitochondrial dysfunction associated with common diseases of aging and genetic mitochondrial diseases, today announced the initiation of IDDEA-HF, a Phase 2 study evaluating elamipretide in patients hospitalized due to congestive heart failure. Heart failure causes more than two million hospitalizations in the U.S. and Europe each year.

“In heart failure, mitochondrial dysfunction may not only be a causative factor, but may also contribute to the progression of the disease and the associated fluid build-up that causes congestion, due to muscle weakness from a lack of energy production,” said Stealth Vice President of Clinical Development Jim Carr. “In line with our findings in elderly patients enrolled in the   trial, we hope to demonstrate the ability of elamipretide to increase energy production to help the heart muscle work better, subsequently relieving congestion in the body.”

IDDEA-HF is a randomized, double-blind, placebo-controlled study to evaluate the cardiac and renal effects of daily treatment with elamipretide in patients who have been hospitalized with congestive heart failure. Up to 300 patients will be randomized within 72 hours of presentation to receive 20 mg daily elamipretide or placebo intravenously for up to seven days. The primary endpoint is change in NT-proBNP, a cardiac biomarker reflecting the level of congestion. Secondary endpoints include change in clinical status and safety and tolerability.

“IDDEA-HF is a key step in our development of therapies for common diseases of aging. These patients have failed current therapies, experiencing an episode of acute decompensation, which highlights the intense need for new options within the heart failure treatment paradigm where we believe elamipretide can have a significant impact,” said Stealth Chief Executive Officer, Reenie McCarthy. “The data from this study, together with our other ongoing trials in heart failure, will help inform our projected Phase 3 heart failure program as well as our approach to other common diseases of aging for which elamipretide may have therapeutic potential.”

IDDEA-HF is the third study Stealth recently initiated to evaluate elamipretide in the heart failure setting. PROGRESS-HF and RESTORE-HF are ongoing Phase 2 randomized, double-blind, placebo-controlled trials to evaluate the effects of four weeks’ treatment with daily subcutaneous injections of elamipretide on left ventricular function in patients with stable heart failure with reduced ejection fraction (PROGRESS-HF) or preserved ejection fraction (RESTORE-HF).

For additional information on or elamipretide, please refer to Stealth’s website and

About Heart Failure

Heart failure affects approximately 21 million people in the United States and Europe, and the incidence is anticipated to increase as the population continues to age. The disease is characterized by a reduced ability to relax and contract the heart to pump blood throughout the body. Heart failure comes in two forms, based on changes in the amount of blood the left ventricle pumps out with each contraction, known as ejection fraction. Both forms, heart failure with reduced ejection fraction and heart failure with preserved ejection fraction, are associated with mitochondrial dysfunction and the resulting lack of energy in the heart muscle. There are currently no FDA-approved treatments for heart failure with preserved ejection fraction, and only limited treatments for heart failure with reduced ejection fraction.

About Elamipretide

Stealth’s lead candidate, elamipretide, is an investigational drug with the potential to modify disease by preserving energetics and restoring normal energy production in mitochondria, while decreasing oxidative stress. The energetics from mitochondria maintain healthy physiology and prevent disease. This mitochondria-targeted candidate is being developed for both rare diseases and common diseases of aging.

Stealth BioTherapeutics: Leading Mitochondrial Medicine

Stealth BioTherapeutics is a privately held biopharmaceutical company committed to bringing mitochondrial therapies to patients to treat both rare diseases and common diseases of aging. Stealth’s clinical development program is focused along several core therapeutic areas, including primary mitochondrial diseases, cardio-renal diseases and ophthalmic disorders. More information regarding Stealth and its pipeline is available at


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