SS-31 (elamipretide)
Approved in 2025 for one rare disease. Failed its larger trial.
Grade B: Some human proof
Small, early or mixed results in people.
The grade is for the use people talk about, not for every use. Filed under: Longevity.
How it works
A tiny peptide that sticks to the inner wall of mitochondria, the cell's power plants.
How it was given in studies
Injection under the skin, in the trials and on the FDA label.
This is what the studies did. It is not a how-to. Source: Trial in 218 patients. Neurology, 2023; FDA label on DailyMed.
What studies saw
FDA gave it early approval in September 2025 for Barth syndrome, a rare genetic disease, based on stronger knee muscles. In a 24-week trial of 218 people with mitochondrial muscle disease, it did not improve walking distance or fatigue.
The trade-off
FDA still requires a trial to confirm it helps patients. None of this is about healthy people or aging.
When it showed up, in studies
No benefit at 24 weeks in the larger trial.
Sources
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Keep going
We show what studies found. We never tell you what to take. Doses vary by study. Check the sources and talk to a doctor.