Most research peptides never leave the lab. SS-31 did more than that. In September 2025, its pharmaceutical form — elamipretide — became the first mitochondria-targeted drug ever to receive FDA approval. That milestone followed more than 20 years of research and over 150 peer-reviewed publications. This overview covers what the published literature shows, and why SS-31 sits in a category of its own.
SS-31 is a small synthetic peptide. It was discovered by accident in a pharmacology lab at Weill Cornell Medicine. What made it remarkable was where it goes: it passes through cell membranes and concentrates in the inner mitochondrial membrane. Few compounds reach that target so selectively.
Because of this targeting, researchers have studied SS-31 under several names over the years — including MTP-131 and Bendavia — before elamipretide became the pharmaceutical name.
Szeto HH. First-in-class cardiolipin-protective compound as a therapeutic agent to restore mitochondrial bioenergetics. Br J Pharmacol. 2014;171:2029-2050.
The central target of SS-31 is cardiolipin. Cardiolipin is an unusual lipid found only on the inner mitochondrial membrane. It plays a structural role in the machinery that produces ATP — the molecule cells use for energy.
When mitochondria are damaged or stressed, cardiolipin becomes disorganized. As a result, energy production drops and harmful byproducts rise. SS-31 binds directly to cardiolipin and helps stabilize this structure. In turn, published models show restored ATP production and reduced oxidative stress.
Elamipretide: A Review of Its Structure, Mechanism of Action, and Therapeutic Potential. Int J Mol Sci. 2025;26(3):944.
SS-31 has been tested in several registered clinical trials. These include PROGRESS-HF in heart failure, MMPOWER-3 in mitochondrial myopathy, ReCLAIM in macular degeneration, and TAZPOWER in Barth syndrome.
The path was not smooth. Several of the larger trials missed their primary endpoints. However, the Barth syndrome program — based on the long-running TAZPOWER trial — showed improvements in muscle strength and cardiolipin levels. On that basis, the FDA granted accelerated approval in September 2025 under the brand name Forzinity.
Reid Thompson W, et al. A phase 2/3 randomized clinical trial to evaluate elamipretide in Barth syndrome. Genet Med. 2021;23:471-478.
Beyond its approved indication, SS-31 has been studied widely in mitochondrial aging models. In aged mice, published research reported improved exercise tolerance, muscle strength, and mitochondrial efficiency after treatment.
Siegel MP, et al. Mitochondrial-targeted peptide rapidly improves mitochondrial energetics and skeletal muscle performance in aged mice. Aging Cell. 2013;12(5):763-771.
Additional studies have examined SS-31 in kidney disease, ischemia-reperfusion injury, neuroinflammation, and pulmonary fibrosis models. Across these, the common thread is the same: protect cardiolipin, and mitochondrial function tends to follow.
| What the Research Doesn’t Say The FDA approval covers Barth syndrome only — a rare disorder affecting roughly 150 people in the United States. It does not establish SS-31 as an approved anti-aging compound. Three of the larger human trials missed their primary endpoints. The published record includes both positive and negative results. Most aging-related findings come from animal and cell models. These do not guarantee the same effects in humans. |
What is SS-31?
SS-31 is a synthetic mitochondrial-targeting peptide. Its pharmaceutical form is called elamipretide, sold under the brand name Forzinity.
What does SS-31 target?
SS-31 targets cardiolipin, a lipid on the inner mitochondrial membrane that is essential for ATP production. By stabilizing cardiolipin, SS-31 supports mitochondrial energy output in published models.
Is SS-31 FDA approved?
Yes, but only for Barth syndrome, a rare mitochondrial disorder. The FDA granted accelerated approval in September 2025. It is not approved as an anti-aging or general wellness compound.
How is SS-31 different from MOTS-C?
Both are mitochondrial peptides, but they work differently. SS-31 stabilizes cardiolipin structure directly. MOTS-C is encoded by the mitochondrial genome and acts as a signaling peptide through AMPK. They address mitochondrial health from different angles.
For informational purposes only. This article is a research literature review. SS-31 is available from Brava Longevity for research use only. Not intended for human or veterinary consumption. Not medical advice.
