MYTX-255

MYTX-255 (formerly SBT-255) is an investigational mitochondrial-targeted peptide therapeutic candidate developed by Mighty Therapeutics (formerly Stealth BioTherapeutics). It is designed to target cardiolipin, a key phospholipid located within the inner mitochondrial membrane that is essential for maintaining mitochondrial structure and bioenergetic function. By binding to cardiolipin, MYTX-255 aims to improve mitochondrial energy-producing capacity, metabolic resilience, and overall mitochondrial function. Mighty Therapeutics is developing MYTX-255 for the treatment of fatty acid oxidation disorders, specifically long-chain fatty acid oxidation disorders (LC-FAODs), and initiated IND-enabling studies in September 2026 with plans to submit an Investigational New Drug (IND) application by year-end 2027. Additionally, MYTX-255 has demonstrated preclinical potential in models of cardiac and muscle myopathy, including hypertrophic cardiomyopathy, idiopathic cardiomyopathy, myocardial infarction, and aging cardiac and skeletal muscle.