SS-31 (elamipretide): research, legal status and who sells it

What it is

SS-31 is elamipretide [8], a peptide that binds cardiolipin, a lipid in the inner membrane of mitochondria, and is being developed for disorders involving mitochondrial dysfunction [9].

Research status

In September 2025, elamipretide received accelerated approval in the US to improve muscle strength in patients with Barth syndrome, an ultra-rare X-linked genetic disorder, becoming the first disease-specific treatment for it [9]. Evidence in Barth syndrome is small: in the open-label extension of the TAZPOWER trial, 8 of 10 participants reached 168 weeks, with improvements in walking distance and some cardiac measures [10]. In a different condition, primary mitochondrial myopathy, the phase 3 MMPOWER-3 trial of 218 people did not meet its primary endpoints for walking distance or fatigue, although the drug was well tolerated [11]. Elamipretide is also in phase 3 development for dry age-related macular degeneration [9].

Regulatory status

The FDA approved elamipretide as Forzinity in September 2025 [1]. No elamipretide medicine is authorized in the UK, the EU or Canada [2][3][4][5]. It is not named in Australia’s Poisons Standard [6] or on WADA’s 2026 Prohibited List [7].

Quality and testing considerations

Forzinity is a prescription product manufactured under FDA oversight [1]. Its approved use is limited to improving muscle strength in adults and children with Barth syndrome who weigh at least 30 kg [9]. Vials sold as “SS-31” by research-chemical vendors are not Forzinity, and their identity, purity and sterility are unverified unless independently tested. A 2026 review of peptides sold directly to patients warned that rigorous human safety data are scarce for unapproved products in this category [8].

Where it’s sold

Outside prescriptions for Forzinity, SS-31 is sold by research-chemical vendors; the tables below track those listings.