Stealth BioTherapeutics Receives FDA Fast Track Designation for Rare Disease Indication

Potential therapeutic for primary mitochondrial myopathy associated with genetic mitochondrial disease

BOSTON – January 7, 2016 – Stealth BioTherapeutics (Stealth), a biopharmaceutical company developing drug candidates for treating mitochondrial dysfunction, today announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation for MTP-131 (also known as Bendavia) for the treatment of primary mitochondrial myopathy, characterized by muscle weakness in patients with genetic mitochondrial diseases. MTP-131 is currently being studied for the treatment of primary mitochondrial myopathy in its MMPOWER trial, with results expected midyear.

Genetic mitochondrial diseases are a diverse group of rare inherited disorders characterized by systemic mitochondrial dysfunction that impairs patient health and well-being. MTP-131 is an investigational drug targeting the inner mitochondrial membrane to help preserve mitochondrial energetics and restore the healthy physiology which is often impaired in many rare and common diseases.

“There are currently no approved therapies for primary mitochondrial myopathy,” said Reenie McCarthy, President of Stealth BioTherapeutics. “The muscle weakness and extraordinary fatigue experienced by these patients make simple daily tasks very challenging. The Fast Track designation acknowledges an understanding of the significant challenges faced by this patient population, and we look forward to working closely with the FDA as we continue to study MTP-131 as a potential therapy.”

The FDA’s Fast Track program facilitates the development and review of drugs to treat serious conditions with unmet medical needs. The designation also provides the opportunity for more frequent meetings with the FDA over the course of development, and allows a drug company to submit individual sections of its New Drug Application (NDA) for review as they are ready, rather than waiting until all sections of the NDA are complete. Further, the designation also increases the likelihood of eligibility for priority review and accelerated approval if relevant criteria are met.

About Bendavia™
Stealth’s lead candidate, Bendavia (MTP-131), 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 mitochondrial-targeted candidate is being developed for both common and rare diseases, including inherited mitochondrial diseases for which there are no FDA-approved treatments. The underlying science is supported by more than 100 publications and abstracts.

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. Stealth’s clinical development program is focused along several core therapeutic areas, including cardio-renal diseases, ophthalmic disorders and orphan mitochondrial diseases.

More information regarding Stealth and its pipeline is available at

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