FDA Grants Rare Pediatric Disease Designation to Stealth BioTherapeutics for Elamipretide for the Treatment of Barth Syndrome

BOSTON, March 3, 2020 /PRNewswire/ -- Stealth BioTherapeutics (NASDAQ: MITO), a clinical-stage biotechnology company focused on the discovery, development and commercialization of novel therapies for diseases involving mitochondrial dysfunction, today announced that the U.S. Food and Drug Administration (FDA) has granted Rare Pediatric Disease (RPD) designation for elamipretide for the treatment of Barth syndrome, an ultra-rare genetic condition.

Under the FDA's RPD designation program, the FDA may grant a priority review voucher to a sponsor who receives approval for a "rare pediatric disease," a serious and life-threatening disease that primarily affects individuals aged from birth to 18 years and fewer than 200,000 people in the United States. Upon FDA approval of elamipretide for Barth syndrome, Stealth BioTherapeutics is eligible for a voucher that can be used to obtain priority review for a subsequent human drug application upon meeting relevant statutory requirements associated with the RPD program. 

"This designation for elamipretide underscores our alignment with the FDA around the significant and urgent unmet medical need for Barth patients," said Reenie McCarthy, Chief Executive Officer of Stealth.  "We hope to improve the healthspan of Barth patients, for whom cardiomyopathy, exercise intolerance and debilitating fatigue limit life expectancy and impair quality of life.  We are also expanding our development efforts to consider trials in patients suffering from overlapping metabolic cardiomyopathies in diseases such as Duchenne and Becker muscular dystrophies, and Friedreich's ataxia."

About Barth Syndrome
Barth syndrome is an ultra-rare genetic condition characterized by cardiac abnormalities often leading to heart failure and reduced life expectancy, recurrent infections, muscle weakness and delayed growth. Barth syndrome occurs almost exclusively in males and is estimated to affect one in 200,000 to 400,000 individuals worldwide. There are currently no FDA- or EMA-approved therapies for patients with Barth syndrome.

About Stealth
We are a clinical-stage biotechnology company focused on the discovery, development and commercialization of novel therapies for diseases involving mitochondrial dysfunction. Mitochondria, found in nearly every cell in the body, are the body's main source of energy production and are critical for normal organ function. Dysfunctional mitochondria characterize a number of rare genetic diseases and are also involved in many common age-related diseases, typically involving organ systems with high energy demands such as the heart, the eye, and the brain. We believe our lead product candidate, elamipretide, has the potential to treat both rare metabolic cardiomyopathies, such as Barth, Duchenne and Becker muscular dystrophies, and Friedreich's ataxia, as well as ophthalmic diseases entailing mitochondrial dysfunction, such as dry age-related macular degeneration and Leber's hereditary optic neuropathy. We are evaluating our second-generation clinical stage candidate, SBT-272, for rare neurodegenerative disease indications following promising preclinical data in amyotrophic lateral sclerosis, or ALS. Our pipeline compounds include SBT-259, which we are evaluating for rare peripheral neuropathies, and the SBT-550 series of compounds, which we plan to evaluate for rare neurodegenerative and ophthalmic indications. We have optimized our discovery platform to identify novel mitochondria-targeted compounds, which may be nominated as therapeutic product candidates or utilized as scaffolds to deliver other compounds to mitochondria. We have assembled a highly experienced management team, board of directors and group of scientific advisors to help us achieve our mission of leading mitochondrial medicine.

Forward-Looking Statements
This press release contains forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Such forward-looking statements include those regarding Stealth BioTherapeutics' plans, strategies and expectations for its advancement of its drug development programs, including its ongoing clinical trials of elamipretide; the potential benefits of Stealth BioTherapeutics' product candidates; its key milestones for 2020; and its plans regarding future data presentations; and its anticipated interactions with regulatory agencies.  Statements that are not historical facts, including statements about Stealth BioTherapeutics' beliefs, plans and expectations, are forward-looking statements. The words "anticipate," "expect," "hope," "plan," "potential," "possible," "will," "believe," "estimate," "intend," "may," "predict," "project," "would" and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Stealth BioTherapeutics may not actually achieve the plans, intentions or expectations disclosed in these forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements as a result of known and unknown risks, uncertainties and other important factors, including: Stealth BioTherapeutics' ability to obtain additional funding; the ability to successfully demonstrate the efficacy and safety of Stealth BioTherapeutics' product candidates and future product candidates; the preclinical and clinical results for Stealth BioTherapeutics' product candidates, which may not support further development and marketing approval; the potential advantages of Stealth BioTherapeutics' product candidates; the content and timing of decisions made by the U.S. FDA, the EMA or other regulatory authorities, investigational review boards at clinical trial sites and publication review bodies, which may affect the initiation, timing and progress of preclinical studies and clinical trials of Stealth BioTherapeutics product candidates; Stealth BioTherapeutics' ability to obtain and maintain requisite regulatory approvals and to enroll patients in its planned clinical trials; unplanned cash requirements and expenditures; competitive factors; Stealth BioTherapeutics' ability to obtain, maintain and enforce patent and other intellectual property protection for any product candidates it is developing; and general economic and market conditions. These and other risks are described in greater detail under the caption "Risk Factors" included in Stealth BioTherapeutics' most recent Annual Report on Form 20-F filed with the Securities and Exchange Commission ("SEC"), as well as in any future filings with the SEC. Forward-looking statements represent management's current expectations and are inherently uncertain. Except as required by law, Stealth BioTherapeutics does not undertake any obligation to update forward-looking statements made by us to reflect subsequent events or circumstances. 

Investor Relations
Stern Investor Relations
Lauren Stival, 212-362-1200
[email protected]

SOURCE STEALTH BIOTHERAPEUTICS INC.