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.
16 vendors tracked by PeptideAtlas list SS-31, priced from $20.00 to $172. The lowest price per milligram is $1.16/mg at Archer Peptides (50MG). 9 independent Janoshik purity tests cover SS-31 across 7 vendors. Results range from 99.6% to 99.9%.
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 113 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.
| Amino-acid sequence | D-Arg-Dmt-Lys-Phe-NH2 (Dmt = 2',6'-dimethyltyrosine) |
|---|---|
| Molecular weight | ~639.8 g/mol |
| CAS number | 736992-21-5 |
| Half-life | ~4 hours |
| Production method | synthetic |
| Anti-doping status | not-listed |
| US regulatory status | FDA-approved (September 2025) as Forzinity for Barth syndrome — first FDA-approved mitochondria-targeted therapeutic. Accelerated approval pathway. FDA Fast Track and Orphan Drug designation. |
| Vendor | Size | Price | Price per mg |
|---|---|---|---|
| Archer Peptides | 50MG | $58.00 | $1.16/mg |
| Prospera Peptides | 10mg | $20.00 | $2.00/mg |
| PureRx Peptides | 50mg | $125 | $2.50/mg |
| Pulse Research Expansion | 50MG | $140 | $2.80/mg |
| The Peptide Labs | 50MG | $140 | $2.80/mg |
| Growth Guys | 50mg | $150 | $3.00/mg |
| Great Northern Peptides | 50mg | $150 | $3.00/mg |
| Red Fox Peptides | 50 mg | $155 | $3.10/mg |
| Compound Purity | 50mg | $172 | $3.44/mg |
| Choice Peps | 10mg | $48.00 | $4.80/mg |
| Pacific Peptide | 10mg | $75.00 | $7.50/mg |
| Sports Technology Labs | 10MG | $79.99 | $8.00/mg |
| Buy Peptides Australia | 10mg | $89.99 | $9.00/mg |
| Lucky Link Peptides | 10MG | $90.00 | $9.00/mg |
| US Peptides | 10mg | $100 | $10.00/mg |
| HK Peptides Worldwide | 5 mg | $87.00 | $17.40/mg |
| Vendor | Best tested purity |
|---|---|
| Imperial Peptides | 99.9% |
| Qingdao Sigma Chemical QSC | 99.9% |
| wslabus | 99.8% |
| Peptide Gurus | 99.7% |
| Zhuoyan Peptides | 99.7% |
| Kensingtonlabs.co | 99.6% |
Related peptides: MOTS-c, 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.
Vendors with independent lab tests for it: Optima Chemical Supplies Inc.
Vendors stocking it: Polar Peptides, Risynth Bio, M-Peptides, Amino Lair, Reta-Peptide, Zztai Peptide, Homopeptide, DH Peps, Biomax Research, Mei Peptide, Pulse Research Expansion, Pacific Peptide, Prospera Peptides, Choice Peps, Compound Purity, Blue Line Research, Legendary Peptides, Charleston Peptide Supply, BioPure Peptides, Archer Peptides, Athena Peptides, PureRx Peptides, RipTidez, Main Peptides, Catalyst Peptides, Tide Labs, Bluewell Peptides, Buy Peptides Australia, uwa-biotech, utherpeptide, Uther, Sports Technology Labs, Disguised Alpha, Growth Guys, Great Northern Peptides, The Peptide Labs, Toronto Peptides, Montreal Peptides, Pure Peptides UK, Advanced Peptides Australia.
Coverage on this site: Anti-Aging Peptides: Research Compounds for Metabolism, Muscle, and Tissue Health.