SS-31 peptide, also called elamipretide, is a mitochondria-targeted research peptide. Learn what studies show, its FDA status, and safety concerns.
SS-31 peptide is a synthetic four-amino-acid compound, also known as elamipretide, that concentrates inside mitochondria and binds to cardiolipin on the inner membrane. It is an investigational peptide drug, not an FDA-approved medication and not a legal dietary supplement in the United States. Human research so far is limited to small trials in Barth syndrome, primary mitochondrial myopathy, heart failure, and dry age-related macular degeneration.
What Is the SS-31 Peptide?
SS-31 was created in the laboratory of Dr. Hazel Szeto at Cornell University. Its chemical sequence is D-Arg-Dmt-Lys-Phe-NH2, which makes it a tetrapeptide — four amino acids linked together.
Scientists describe it as mitochondria-targeted because it accumulates in mitochondria instead of distributing evenly through tissue. In medical literature, the same molecule is usually called elamipretide.
SS-31 is not related to BPC-157, TB-500, or collagen peptides, even though online sellers sometimes group them together. People researching tissue repair often also read about bpc-157 peptide for inflammation, but the two compounds act on different biology.
How SS-31 Works at the Cellular Level
Mitochondria generate ATP, and their inner membrane depends on cardiolipin to organize the proteins that produce energy. When cardiolipin oxidizes, membranes lose structure, energy output falls, and reactive oxygen species rise.
SS-31 binds cardiolipin and appears to stabilize the membrane. In cell and animal models, that interaction has been associated with:
- Reduced reactive oxygen species
- More efficient ATP production
- Less cell death after ischemia-reperfusion injury
- Improved insulin sensitivity in some metabolic studies
These results come from laboratory and animal work. They suggest a mechanism of action but do not demonstrate that SS-31 treats human disease.
What Human Trials Have Found
Clinical research on elamipretide has been small and condition-specific.
Barth syndrome
Barth syndrome is a rare genetic disorder that affects cardiolipin metabolism. Small open-label studies reported improvements in some functional measures, but an FDA advisory committee voted against recommending approval in 2024, citing limited evidence of benefit.
Primary mitochondrial myopathy
The MMPOWER trial tested elamipretide in people with mitochondrial myopathy. It did not meet its primary endpoint on the six-minute walk test, although some secondary measures moved in a positive direction.
Heart failure and eye disease
Early-phase studies have examined elamipretide in heart failure and dry age-related macular degeneration. Results have been mixed, and no large confirmatory trial has established a clear clinical benefit.
How SS-31 Compares With Other Popular Peptides
| Compound | Main research focus | Human evidence | US regulatory status |
|---|---|---|---|
| SS-31 (elamipretide) | Mitochondrial dysfunction | Small Phase 2–3 trials; mixed results | Not FDA-approved |
| BPC-157 | Tissue repair and inflammation | Mostly animal data | Not FDA-approved for human use |
| TB-500 | Soft-tissue repair | Early and animal studies | Not FDA-approved for human use |
| GHK-Cu | Skin remodeling and wound healing | Topical cosmetic research | Used as a cosmetic ingredient |
Direct comparison is difficult because these compounds act on different pathways and carry different amounts of human data. Only SS-31 has reached late-stage FDA review, and that review did not result in approval.
FDA Status and Legal Reality
Elamipretide has not been approved by the FDA for any indication in the United States. Any product marketed as SS-31 for human consumption is therefore unapproved.
The compound is widely sold online as "research grade" powder or liquid. Those products are not manufactured under sterile pharmaceutical standards, and their labels typically state they are not for human use.
This regulatory gap shapes peptide drug development across the field: a promising molecule can spend a decade in trials and still lack an approved product, while unregulated copies appear online long before the science settles.
Safety and Side Effects
In published trials, reported side effects included injection-site reactions, headache, nausea, and dizziness. Short-term use was generally described as tolerable, but long-term safety data are thin.
Risks increase sharply when people buy unregulated vials. Sterility, actual peptide content, and accurate dosing are not guaranteed by online sellers.
Anyone with a mitochondrial or cardiac condition should talk with a physician before considering an investigational peptide. Self-dosing an unapproved injectable is not a low-risk decision.
SS-31 and the Supplement Market
SS-31 is not one of the natural peptide supplements you will see on a legitimate label, because it is a synthetic drug-style molecule rather than a nutrient.
People who type peptide injections for skin near me are usually looking at collagen, GHK-Cu, or med spa offerings that have nothing to do with mitochondrial research.
Mixing up those categories leads to bad decisions. A topical peptide cream marketed for wrinkles is not the same product as an injectable investigational drug, and the evidence base for each is completely different.
Bottom Line
SS-31 is a mitochondria-targeted tetrapeptide with a plausible mechanism and incomplete human evidence. Elamipretide has not been approved by the FDA for any medical use in the United States.
No completed trial has shown that SS-31 reverses mitochondrial disease, heart failure, or aging. Research-grade products sold online are unapproved for human use and carry contamination and dosing risks.
The reasonable next step for anyone curious about SS-31 is a conversation with a licensed healthcare professional, not a purchase from an unverified vendor.
Frequently Asked Questions
What is the SS-31 peptide used for?
SS-31, or elamipretide, is studied for conditions linked to mitochondrial dysfunction, including Barth syndrome, primary mitochondrial myopathy, heart failure, and dry age-related macular degeneration. It is not approved to treat any condition in the United States. Available human data come from small trials with mixed results.
Can you buy SS-31 peptide in the US?
No FDA-approved SS-31 product exists, so vials sold online are labeled for research use only and not for human consumption. These products may be non-sterile or contain less peptide than the label claims. Using them for injection is risky and not legal for human use.
Is SS-31 the same as elamipretide?
Yes. Elamipretide is the clinical and brand-development name for the same molecule that researchers call SS-31. It is also described as a mitochondria-targeted tetrapeptide, with the sequence D-Arg-Dmt-Lys-Phe-NH2.
This page provides educational research information and does not replace medical advice, diagnosis, or treatment.