After earlier regulatory challenges including a complete response letter in May, the FDA has granted accelerated approval to Stealth BioTherapeutics’ elamipretide (Forzinity) for treating Barth syndrome. The approval marks a milestone for this ultra-rare pediatric mitochondrial disorder characterized by muscle weakness and cardiomyopathy. The development journey spanned several years, and the FDA’s green light affirms the drug’s clinical efficacy in improving muscle function in affected patients. This first approved therapy offers hope to a patient population with significant unmet medical needs.