Peptide Science Desk

Forzinity (elamipretide, SS-31)

Also called SS-31. FDA-approved in 2025 as Forzinity, but only for a rare disease called Barth syndrome. It is not approved for anti-aging.

AI illustration of a vial labeled Elamipretide
AI illustration
FDA statusFDA approved

The FDA approved it as a prescription medicine for certain uses.

Proof it works in people for Barth syndrome (a rare disease)Early

Approval was based on an early sign in a very small trial.

Safety data in peopleLimited

Small groups, plus about 200 people in another trial.

These are 3 different questions. FDA status is about the law. Proof is about whether it works. Safety data is about how much we know about its risks. A lack of safety data does not mean it does not work, and "not approved" does not mean "illegal."

By the Peptide Science Desk Editorial TeamFact-checked against FDA and official sources · Not yet reviewed by a licensed clinician. How we check facts

What is it?

Elamipretide is a lab-made peptide. It targets mitochondria, the tiny power plants inside your cells. Online it is often called SS-31. The brand is Forzinity. You need a prescription.

Why do people use it?

Forzinity is approved to improve muscle strength in people with Barth syndrome who weigh at least 66 pounds (30 kg). Barth syndrome is a rare disease people are born with. It weakens the heart and muscles. Online, some people use SS-31 hoping to slow aging. That is not approved.

Does it really work?

The FDA approved it on September 19, 2025, under "accelerated approval." That means the FDA approved it based on an early sign (stronger knee muscles). The company must still prove real benefit in another study.

Studies in people

StudyPeopleWhat they foundLimits
Randomized crossover trial + open-label12Main goals were not met in the first 12 weeks. Walking got better later, when everyone got the drug.Tiny. The later part had no placebo.
Randomized trial (MMPOWER-3, other disease)218No better than placebo for walking or tiredness.Adults with a mitochondrial muscle disease, not Barth.
Randomized trial (one dose)39 older adultsRaised muscle energy right after the dose. No change in muscle tiredness.One dose. One hand muscle. Gone by day 7.
Mouse study (10 months)Older miceBetter heart function; other gains differed in males and females.Mice, not people.
Mouse study (8 weeks)Older miceLess frailty and better heart and muscle, but no change in DNA-based "age" tests.Mice, not people.

Trials listed on ClinicalTrials.gov

We only list studies we read on PubMed or ClinicalTrials.gov. Checked October 18, 2026.

Is it safe? Side effects

  • The most common side effects on the label are reactions where the shot goes in.
  • The label warns about allergic reactions, some serious.
  • It contains benzyl alcohol, so the label says not to use it in newborns.

Banned in sports? Drug tests

Not named on the banned list.

Elamipretide (Forzinity) is not named on WADA's 2026 list. It is an approved medicine, so the "not approved" rule (S0) does not fit. But WADA says its list is not complete. Check it on GlobalDRO.com or ask USADA.

Check work, NCAA, and military rules for Forzinity

SS-31 (elamipretide) and aging

Microscope image of round, oddly shaped mitochondria inside a mouse liver cell
Mitochondria, the "power plants" of cells, seen with an electron microscope. These are from a mouse with a mitochondria disease.Photo: National Institutes of Health, public domain

How does SS-31 work?

  • SS-31 is a small lab-made peptide. Its drug name is elamipretide. It sticks to cardiolipin, a fat inside mitochondria, the power plants of your cells.

What is Forzinity approved for?

  • Forzinity is approved to improve muscle strength in people with Barth syndrome who weigh at least 66 pounds (30 kg). The FDA used "accelerated approval," so the company must still prove real benefit in another study.
  • "SS-31" sold online for research or anti-aging is not the approved medicine.

Does SS-31 help with aging?

  • In 39 healthy adults aged 60 to 85 with weak mitochondria, one dose raised muscle energy right after the drip. A week later, the effect was gone. Muscles did not get less tired.
  • In mice, months of SS-31 helped heart and muscle in old age. A 2025 mouse study found it did not change DNA-based tests of "biological age."
  • A big trial in people with mitochondrial muscle disease (218 people) did not meet its main goals.

Talk to your doctor

Do not start any peptide on your own. Ask a doctor first. We never share doses or tell you where to buy. Print our doctor questions sheet.

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More questions

Is SS-31 the same as elamipretide?

Yes. SS-31 is the lab code name for elamipretide, the medicine in Forzinity.

Does SS-31 help with aging?

Not proven. It is approved only for Barth syndrome. In a trial of 218 adults with a mitochondrial muscle disease, it did not beat placebo.

Is "SS-31" sold online the same as Forzinity?

No. "SS-31" sold for research or anti-aging is not the approved medicine.

Is SS-31 the same as Forzinity?

Same drug, but not the same product. Forzinity is the FDA-approved medicine. "SS-31" sold online for research is not checked by the FDA.

Can a doctor prescribe elamipretide for aging?

Doctors can generally prescribe an approved drug for other uses ("off-label") if they think it is right for you. But no study has shown it slows aging in people.

Does SS-31 reverse biological age?

Not in the tests so far. In a 2025 mouse study, it helped heart and muscle, but DNA-based "age" tests did not change.

What are the side effects of elamipretide?

The Forzinity label lists reactions where the shot goes in as most common. It also warns about allergic reactions, some serious.

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Sources

Not medical advice. Medical disclaimer.