SS-31 peptide is a short chain of four amino acids that is designed to reach mitochondria, the parts of cells that make energy. Its drug name is elamipretide. It has been tested in people with certain rare diseases. For other uses, including aging and athletic performance, human evidence is missing.
The sections below explain what SS-31 is, how it works, and what the trials found.
Key takeaways
- SS-31, elamipretide, MTP-131 and Forzinity all refer to the same compound.
- It is designed to bind a fat molecule inside mitochondria that helps them make energy.
- Most human trials focused on rare diseases, mainly Barth syndrome.
- Trial results have been mixed, and no trials have tested it in healthy adults.
What Is SS-31 Peptide?
SS-31 is a synthetic peptide. A peptide is a short chain of amino acids, the building blocks of protein, and SS-31 has four of them. It was developed by Stealth BioTherapeutics.
The compound has several names, which causes confusion:
- SS-31: the original research name.
- Elamipretide: the official drug name.
- MTP-131 and Bendavia: older development names.
- Forzinity: a brand name used for the drug form developed for Barth syndrome.
When a website sells “SS-31,” it is not the same thing as a drug-grade product. Research-grade vials are made and checked in a different way.
How Does SS-31 Work?
Mitochondria are the power plants of a cell. They turn food into usable energy. Inside each one, an inner membrane holds the machinery that makes that energy.
A fat molecule called cardiolipin acts like scaffolding for that machinery. It keeps the parts in the right place so they can pass energy along smoothly. SS-31 is designed to bind to cardiolipin and help keep that system stable.
A simple comparison: picture a power line with a loose wire that leaks sparks. SS-31 is meant to help hold the wire in place so less energy is lost. Early work described it as an antioxidant, but researchers now think it works mainly by supporting how mitochondria are built and run. Mitochondria also depend on helper molecules, and the role of NAD in cell energy is a good example.
This is the proposed mechanism. How strongly it explains results in people is still being studied.
What Does the Research Say?
| Study | Study type | Key finding |
|---|---|---|
| TAZPOWER, 2021 | Randomized, placebo-controlled human trial in Barth syndrome, then open-label | The randomized phase did not show a clear benefit on its main measures. |
| TAZPOWER extension, 2024 | Human open-label extension (no placebo group) | Researchers reported gains in muscle strength and walking over about three years. |
| MMPOWER-3, 2023 | Human phase 3 trial in primary mitochondrial myopathy (218 people) | Did not meet its main goals. |
| Dry age-related macular degeneration trial | Human trial | Reported as missing its main overall goal. |
A few points keep these results in proportion:
- Every trial enrolled people with disease. None tested healthy adults.
- Open-label results can look better than placebo-controlled ones, because patients and doctors know who gets the drug.
- Experts disagree about how strong the Barth syndrome evidence is, because the later gains came from an open-label extension.
Researchers who work with compounds like this usually source them from trusted platforms such as PeptidePro and ask for a certificate of analysis, or COA. A COA is a lab report that shows what is in the vial and how pure it is.
Does SS-31 Help With Aging or Muscle?
No human trial has shown that. Online claims often point to the Barth syndrome results, but that is a different situation. Barth syndrome is caused by a gene fault that disrupts cardiolipin. Healthy muscle is not.
Researchers are looking at SS-31 in other diseases, such as heart and kidney conditions, but results so far are limited. Other peptides marketed for aging face the same gap between claims and trial data, as in epithalon research.
What can be said:
- It has been tested in people with specific mitochondrial diseases.
- It has not been tested to see if it slows aging.
- It has not been tested to see if it improves performance in healthy people.
SS-31 vs MOTS-c: What Is the Difference?
Both are called mitochondrial peptides, but they are very different.
| SS-31 | MOTS-c | |
|---|---|---|
| Source | Made in a lab | Made by mitochondria themselves |
| Size | Four amino acids | Sixteen amino acids |
| Main idea | Supports the inner membrane that makes energy | Acts as a signal that affects how cells use fuel |
| Human trial data | Several disease trials | Very limited |
MOTS-c has far less human data than SS-31, so it is not a like-for-like comparison.
SS-31 Side Effects and Safety in Studies
In the Barth syndrome trials, the most common side effects were mild to moderate reactions at the injection site, such as redness or soreness. Longer-term safety data come from small groups of patients with disease.
What is still unknown:
- Safety in healthy adults, who have never been studied
- Long-term effects beyond a few years of follow-up
- Quality and purity of research-grade vials sold online
The wider question of whether peptides are safe has no single answer, because it depends on the compound and the context.
Is SS-31 Allowed in Sport?
Anti-doping rules change over time. Athletes should check the current WADA Prohibited List instead of relying on a general article.
FAQs
What is SS-31?
SS-31 is a synthetic four-amino-acid peptide designed to bind cardiolipin, a fat molecule inside mitochondria. It is also called elamipretide. It has been tested in people with rare mitochondrial diseases. Other uses have not been proven in trials.
Has SS-31 been tested in humans?
Yes, in people with certain rare diseases, including Barth syndrome and primary mitochondrial myopathy. Results have been mixed. No trials have tested it in healthy adults, so its effects on aging or performance are unknown.
Is SS-31 the same as elamipretide?
Yes. SS-31 is the original research name, and elamipretide is the official drug name. It was also called MTP-131 and Bendavia in development. Forzinity is a brand name used for the drug form.
How does SS-31 affect mitochondria?
It is designed to bind cardiolipin, a fat molecule on the inner mitochondrial membrane that holds energy-making machinery in place. The idea is that this keeps the system stable and reduces energy leakage. This is a proposed mechanism, still under study.
Is SS-31 the same as MOTS-c?
No. SS-31 is a lab-made four-amino-acid peptide. MOTS-c is a longer peptide made by mitochondria themselves. Both are linked to mitochondrial function, but they work in different ways and have very different amounts of human trial data.
This content is for educational and research purposes only. The compounds discussed are not intended for human consumption. Nothing here is medical advice. For any peptide use, readers should consult an expert who can advise what works best for them.