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Peptides / SS-31 (elamipretide) / United States

SS-31 (elamipretide) in the United States

Legal status, what it is, and the listed suppliers in the United States that list it.

Legal status in the United States

Approved medicine (accelerated approval, 19 September 2025) as Forzinity for Barth syndrome in adults and children weighing at least 30 kg. Not approved for any other use.

As understood at 2026-09-22. Verify with the FDA.

What SS-31 (elamipretide) is

SS-31, known as elamipretide in clinical development, is a synthetic four-amino-acid peptide that concentrates in mitochondria and binds cardiolipin, a lipid of the inner mitochondrial membrane. It was developed by Stealth BioTherapeutics. In September 2025 the US FDA granted it accelerated approval, under the brand name Forzinity, for Barth syndrome, a rare genetic mitochondrial disease. That is the only approved use; its other studied uses remain investigational.

Full SS-31 (elamipretide) page: targets and research →

Listed suppliers in the United States

4 of the 10 suppliers we list in the United States list SS-31 (elamipretide). Listed, not endorsed: each row is the supplier’s own stated terms.

Direct Peptides United States All products are sold strictly for laboratory research use only and are not for human or animal consumption. Direct Peptides is a chemical supplier, not a compounding pharmacy or 503A/503B facility. HEEZ Research United States All products are for laboratory developmental research use only. Products are not for human consumption. HEEZ Research is a chemical supplier. Nationwide Peptides United States For Research Use Only. Products are not intended for human or animal consumption, ingestion, injection, or any form of administration. Peak Lab Peptides United States All products on this site are for research and development use only. Products are not for human consumption of any kind.

Clinical Research

Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical Trial
Karaa A, Bertini E, Carelli V, et al. (MMPOWER-3 Trial Investigators) (2023). Neurology. human adults with genetically confirmed primary mitochondrial myopathy, phase 3, n=218
Long-term efficacy and safety of elamipretide in patients with Barth syndrome: 168-week open-label extension results of TAZPOWER
Thompson WR, Manuel R, Abbruscato A, et al. (2024). Genetics in Medicine. human people with Barth syndrome, open-label extension, n=10 (8 reached week 168)
Expanded-access use of elamipretide in a newborn with Barth syndrome: a case report
Ortmann L, Velasco D, Cole J (2025). European Heart Journal - Case Reports. human single newborn with Barth syndrome, case report
Elamipretide: A Review of Its Structure, Mechanism of Action, and Therapeutic Potential
Tung C, Varzideh F, Farroni E, et al. (2025). International Journal of Molecular Sciences. review n/a (review)