Stealth BioTherapeutics has announced that the U.S. Food and Drug Administration (FDA) has granted accelerated approval to Forzinity (elamipretide HCl), marking it as the first approved therapy for Barth syndrome. This ultra-rare genetic mitochondrial disorder primarily affects males and is characterized by severe heart failure, muscle weakness, and fatigue. The condition often leads to premature death, with survivors typically experiencing significant health challenges.
Forzinity is administered as a once-daily subcutaneous injection and is approved for use in adult and pediatric patients weighing at least 30 kilograms (approximately 66 pounds). The FDA’s decision was based on clinical evidence demonstrating improved knee muscle strength, a marker considered reasonably likely to predict broader functional benefits, such as enhanced mobility and reduced fatigue. The approval was granted under the FDA’s accelerated approval pathway, which allows earlier approval of medications that treat serious conditions and fill an unmet medical need.
As part of the accelerated approval, Stealth BioTherapeutics is required to conduct a post-marketing trial to confirm the clinical benefits of Forzinity. If the confirmatory trial fails to verify the drug’s effectiveness, the FDA could revoke market approval. The company has indicated plans to continue providing expanded access to children weighing less than 30 kilograms who are currently receiving treatment or require emergency access, while working with the FDA to generate data needed to expand the indication to include these children.
Barth syndrome is an ultra-rare genetic mitochondrial disease leading to exercise intolerance, muscle weakness, debilitating fatigue, heart failure, recurrent infections, and delayed growth. The disease is associated with reduced life expectancy, with 85% of early deaths occurring by age five. Barth syndrome occurs primarily in males and is estimated to affect one in 1,000,000 males worldwide or around 150 individuals in the United States.
