Stealth BioTherapeutics Presents at 2015 United Mitochondrial Disease Foundation National Symposium

Orphan mitochondrial disease program highlighted during annual meeting

Boston, MA – June 22, 2015 – Stealth BioTherapeutics (Stealth), a biopharmaceutical company developing drug candidates for treating mitochondrial dysfunction, provided a development update for its investigational drugs, Bendavia and Ocuvia, and announced future clinical plans for its orphan mitochondrial disease program at the 2015 United Mitochondrial Disease Foundation (UMDF) National Symposium in Washington, D.C. UMDF is a leading patient advocacy organization for those with inherited mitochondrial diseases, promoting patient-focused research and education, and supporting its members and their families. Inherited mitochondrial diseases encompass a diverse group of rare genetic disorders caused by mitochondrial dysfunction that severely impair patient well-being and quality of life.

During the National Symposium, Stealth updated UMDF participants on the progress of its MMPOWER study for Mitochondrial Myopathy (MM) and announced plans to initiate a broader MM patient trial. Stealth’s MMPOWER study is investigating Bendavia for the treatment of MM (muscle weakness) in patients with genetic mitochondrial diseases. MM is an important component of most mitochondrial diseases—characterized by muscle weakness and impaired exercise capacity, which leads to extraordinary fatigue.

“The current treatment options for mitochondrial diseases are limited to vitamins and supplements. Without investigational drugs such as Bendavia, there would be no prospect for effective therapies to help the children and adults we represent,” commented Charles Mohan, Executive Director of UMDF.

Stealth also detailed its plans to initiate a clinical study in inherited optic neuropathies with its ReSIGHT trial for Leber’s Hereditary Optic Neuropathy (LHON). LHON is a rare genetic mitochondrial disease and the most common inherited optic neuropathy, causing sudden and permanent loss of vision, predominately in young men. Lissa Poincenot, a leading LHON patient advocate, remarked, “We are tremendously excited for Ocuvia’s potential to treat devastating optic neuropathies and improve the lives of our patients.”

Bendavia and Ocuvia each target dysfunction in the inner mitochondrial membrane to treat diseases both common and rare, including cardio-renal diseases, ophthalmic disorders and orphan mitochondrial diseases. In studies, Bendavia and Ocuvia modify disease progression by restoring cellular energetics and function. To date, these investigational drugs are well-tolerated, demonstrating patient benefit in clinical studies directed by leading clinicians across several therapeutic areas.

“There are more than 270 orphan mitochondrial diseases and no FDA-approved treatments. The impact of these diseases on patient quality of life is very real,” said Chief Executive Officer Travis Wilson. “By focusing on mitochondrial myopathy and inherited optic neuropathies with Bendavia and Ocuvia, we are addressing important orphan disorders with a mitochondrial genetic basis. We are committed to our rare mitochondrial disease program in hopes of providing patients with the first FDA-approved therapy.”

For additional information on Bendavia or Ocuvia, and details regarding eligibility for Stealth’s clinical trials in inherited mitochondrial diseases, please refer to 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 Mitochondrial Myopathy

Inherited mitochondrial diseases often cause patients prominent muscle damage or weakness termed Mitochondrial Myopathy. There are more than 270 genetic mitochondrial diseases with nearly 40,000 patients worldwide suffering from Mitochondrial Myopathy. These rare diseases are caused by mutations, or changes, in genes that affect mitochondrial capacity and quality, diminishing patient quality of life.

About Mitochondrial Optic Neuropathies

Mitochondrial optic neuropathies include a broad group of orphan genetic diseases that cause vision loss due to mitochondrial dysfunction. Affecting more than 1 in 10,000 individuals, optic neuropathies are common to over 20 inherited mitochondrial diseases.

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 inherited 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 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 an important and 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’s clinical development program is focused along several core 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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