Stealth BioTherapeutics Initiates a Clinical Study of Bendavia for the Treatment of Orphan Mitochondrial Diseases

Trial is one of the first to study Mitochondrial Myopathy, a disorder common to over 270 genetic mitochondrial diseases

Boston, MA – February 17, 2015 – Stealth BioTherapeutics (Stealth) today announced the initiation of a clinical study of Bendavia in patients with Mitochondrial Myopathy (MM). This study will investigate Bendavia for the treatment of myopathy (muscle weakness) in patients with genetic mitochondrial diseases. Genetic mitochondrial diseases are a diverse group of rare inherited disorders characterized by systemic mitochondrial dysfunction that impairs patient health and wellbeing. Bendavia is an investigational drug that targets the inner mitochondrial membrane to treat diseases both common and rare, including cardio-renal diseases and orphan mitochondrial diseases.

“There are more than 270 orphan mitochondrial diseases and no FDA-approved treatments. The impact these diseases have on quality of life and patient health is very real,” said Dr. Bruce H. Cohen, Director of Pediatric Neurology at Akron Children’s Hospital. “By targeting mitochondrial myopathy, we are addressing an important component of these disorders: muscle loss and impaired exercise capacity accompanied by extraordinary fatigue. Mitochondrial myopathy impairs patients’ ability to perform simple daily activities, greatly diminishing their quality of life.”

To date, Bendavia has been well-tolerated in multiple Phase 1 and 2 clinical trials and studied extensively by leading clinicians and researchers across the spectrum of disease. In nonclinical studies, Bendavia has been shown to modify disease by targeting the inner mitochondrial membrane and restoring cellular energetics and function.

“We are aggressively focused on pursuing our orphan MM program in the hopes of providing patients with the first FDA-approved therapy for inherited mitochondrial diseases,” said Chief Executive Officer Travis Wilson. “We look forward to initiating this trial and evaluating its benefits in this underserved patient population.”

Mitochondrial Myopathy (MM) Trial Design

Stealth’s MM trial will evaluate ascending doses of Bendavia in patients across several clinical sites in the United States. Eligible participants will be between the ages of 16 and 65 and have a genetically-confirmed mitochondrial disease with MM. Endpoints for the MM trial are safety, tolerability and efficacy, including exercise capacity and testing.

“This trial is an important step in our pursuit of therapies for children and adults affected by mitochondrial diseases, including MELAS, Leigh’s, MERRF and many other disorders,” Cristy Balcells, Executive Director at MitoAction, said.

“The current treatment options are limited mainly to vitamins and supplements, so the patient community’s participation in clinical trials is critical. Without trials like this one, there will be no effective patient therapies,” added Charles Mohan, Executive Director of UMDF.

For additional information on this study, its clinical sites or Bendavia, please refer to Stealth’s website and

Mitochondria, The Cell’s Powerhouse

Mitochondria are the cell’s powerhouse, responsible for more than 90% of the energy our bodies need to sustain life and support growth. The energetics from mitochondria maintain healthy physiology and prevent disease. In many common and rare diseases, dysfunctional mitochondria are a key component of disease progression.

About Bendavia™ and Ocuvia™

Stealth’s lead candidates, Bendavia and Ocuvia, are investigational drugs with the potential to modify disease through mitoprotection — the ability to preserve energetics and restore normal energy production in mitochondria, while decreasing oxidative stress. These clinical candidates are being developed for both common and rare diseases including mitochondrial diseases where there are no FDA-approved treatments. The underlying science of Bendavia and Ocuvia is supported by more than 100 independent, peer-reviewed publications and abstracts. These mitochondrial-targeted candidates represent a novel therapeutic approach with the potential to address a wide variety of diseases having unmet treatment needs.

Stealth BioTherapeutics: Leading Mitochondrial Medicine

Stealth BioTherapeutics is a privately held biopharmaceutical company committed to bringing mitochondria therapies to patients to treat both common and rare diseases. As a key common element in a variety of serious, debilitating diseases, mitochondria — the cell’s energy source — offer a promising, and yet untapped, target to modify diseases with significant unmet treatment needs. Stealth is expanding its clinical development program to additional therapeutic areas, including cardio-renal diseases, ophthalmic disorders and orphan mitochondrial diseases. By defining the broad potential of its mitochondrial platform and therapies, Stealth is leading mitochondrial medicine.

More information regarding Stealth and its pipeline is available at

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