SS-31 (Elamipretide) is a mitochondria-targeted tetrapeptide that selectively concentrates in the inner mitochondrial membrane, binding to cardiolipin and stabilizing cristae structure. It is being developed by Stealth BioTherapeutics for mitochondrial diseases, heart failure, and age-related mitochondrial dysfunction. It has undergone multiple Phase I–III clinical trials, including the TAZPOWER trial for Barth syndrome.
Category: Metabolic / Mitochondrial. Evidence rating: A (strong human clinical data).
Clinical status: FDA-approved (Forzinity, September 2025) for Barth syndrome. Phase II (heart failure, renal dysfunction, age-related macular degeneration).
SS-31 is a cell-permeable peptide with an alternating aromatic-cationic motif (D-Arg-Dmt-Lys-Phe-NH2) that allows it to cross membranes without a carrier. It concentrates >1000-fold in mitochondria, where it binds to cardiolipin on the inner mitochondrial membrane. This stabilizes the electron…
Research base: 0 registered clinical trials and 109 indexed publications reference SS-31.
Safety considerations: Generally well-tolerated in clinical trials at tested doses; Common: injection site reactions (pain, redness); Mild headache, dizziness, and nausea reported.
Reviewed by the PeptideAtlas Editorial Team. Last reviewed: 2026-07-05.
Related peptides: MOTS-c, Humanin.
Compare: SS-31 vs MOTS-c, SS-31 vs Humanin.
SS-31 concentrates directly in mitochondria (>1000x enrichment) and prevents ROS formation at the electron transport chain, rather than scavenging free radicals after they form. This targets the source of oxidative stress, making it far more efficient than oral antioxidants like vitamin C or E.
Yes, as of September 2025. SS-31 (Elamipretide) was granted accelerated approval under the brand name Forzinity for Barth syndrome, making it the first FDA-approved mitochondria-targeted therapeutic. It remains investigational for other indications including heart failure and age-related macular degeneration.
SS-31 (Elamipretide) is a mitochondria-targeted peptide researched for its ability to improve cellular energy production and protect against oxidative stress.
SS-31 (ELAMIPRETIDE) has been studied for: Mitochondrial function, Cellular energy, Oxidative stress protection, Tissue repair. Cellular energy repair; mitochondrial targeting.
Targets cardiolipin in mitochondrial membrane, optimizing electron transport chain function and reducing reactive oxygen species.