Aging & longevity · Muscle & recovery

SS-31, simplified.

Also called Elamipretide, Forzinity

Approved Rx

A mitochondria-protecting peptide that became the first approved treatment for a rare genetic disease in 2025.

Size
4 amino acids
How it is taken
Daily injection
Status
FDA-approved for one rare disease

What is it?

SS-31 sticks to the inner wall of mitochondria and helps keep their energy machinery working.

What studies show

What we don’t know yet

Side effects and cautions

Is it legal?

Common questions

What is SS-31?

A mitochondria-protecting peptide that became the first approved treatment for a rare genetic disease in 2025. SS-31 sticks to the inner wall of mitochondria and helps keep their energy machinery working.

What does the research say about SS-31?

It received accelerated FDA approval in 2025 for Barth syndrome, a rare inherited disease that weakens muscles and the heart. A larger trial in another mitochondrial disease missed its main goal.

Is SS-31 FDA approved?

FDA-approved only for Barth syndrome.

What are the side effects of SS-31?

Injection-site reactions are common.

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This page explains published research in plain language. It is not medical advice, a diagnosis, or a recommendation to take anything, and it does not give dosing. Most peptides here are not FDA-approved, and products sold online vary widely in purity. Rules around peptides are changing, so check the current status and talk with a licensed clinician before starting anything. Last reviewed 2026-09-26.