SS 31 FDA Approval: Has Elamipretide Been Approved?

SS 31 has not received FDA approval. Elamipretide, the drug candidate most people mean when they say SS-31, is still an investigational compound in the United States, and the FDA has not authorized it for Barth syndrome, primary mitochondrial myopathy, heart failure, or any other condition. Every SS-31 product sold online today is marketed as a research chemical, not as an approved medicine.

What Is SS-31 (Elamipretide)?

SS-31 is a synthetic tetrapeptide engineered to concentrate inside mitochondria. Its four-amino-acid chain carries a positive charge that lets it dock onto cardiolipin, a phospholipid on the inner mitochondrial membrane.

The compound was developed by Stealth BioTherapeutics and appears in the scientific literature under several names:

• SS-31 — the original research designation
• Elamipretide — the international nonproprietary name
• MTP-131 and Bendavia — earlier development names

Scientists study the ss 31 peptide mainly in models of mitochondrial dysfunction, including rare genetic disorders, heart failure, and age-related muscle decline.

SS-31 FDA Approval Status: A Timeline

The FDA has not approved SS-31 for any human indication. The program stalled on the strength of the clinical evidence, not on a single safety signal.

Indication	Key Trial	Result	FDA Status
Barth syndrome	TAZPOWER (open-label, about 10 patients)	Improvements in some functional measures; no randomized confirmation	Not approved; advisory committee voted against approval in October 2024
Primary mitochondrial myopathy	MMPOWER-3 (randomized Phase 3)	Missed its primary endpoint	Not approved
Heart failure and other conditions	Early-phase studies	Mixed or inconclusive	Not approved

Elamipretide has received orphan drug and rare pediatric disease designations for Barth syndrome. Those designations create development incentives, and they are not approvals.

Why the FDA Has Not Approved SS-31

FDA approval of a new drug generally requires substantial evidence from adequate and well-controlled trials. The SS-31 program has not met that bar.

• Small study populations. Barth syndrome is extremely rare, so trials enroll very few patients.
• Open-label designs. Without a placebo control, improvements can reflect expectation or natural variation.
• Unclear endpoints. It has been difficult to show that measured changes translate into meaningful clinical benefit.
• No confirmatory trial. A large randomized study has not reproduced the early signals.

A negative advisory committee vote does not legally bind the agency, but it usually makes approval unlikely without new data.

Can You Buy SS-31 Legally in the United States?

You cannot buy an FDA-approved SS-31 product, because no approved product exists. What is available online is a research-grade chemical labeled "not for human consumption."

Vendors selling these compounds operate outside FDA oversight. There is no independent verification of identity, purity, sterility, or actual peptide content, and no requirement to report adverse events.

Selling a research chemical is not the same as selling an approved drug, and importing it for personal medical use is not permitted under federal law. Researchers who buy ss-31 peptide for laboratory work typically request a certificate of analysis from the supplier.

What Research Suggests About SS-31 Benefits

Most evidence for ss-31 benefits comes from cell and animal studies. In those models, the peptide has been linked to reduced oxidative stress, better mitochondrial energy production, and less tissue damage after ischemia.

Human data remain limited. Trials have produced changes on some functional and biomarker measures, but not the consistent, clinically meaningful improvement regulators expect.

Because both compounds target mitochondrial biology, researchers often study ss-31 and mots-c together. MOTS-c is a different peptide with a different mechanism, and results from one do not transfer to the other.

Dosing, Reconstitution, and Safety

There is no FDA-approved dose of SS-31, because there is no approved product. Any SS-31 dosing schedule circulating online is borrowed from laboratory work or from trials conducted in supervised clinical settings.

Information about ss-31 reconstitution and dosage typically describes dissolving lyophilized powder in bacteriostatic water for lab use. That is a handling procedure, not a medical recommendation. Doses used in human trials were given under medical supervision with monitoring.

Reported side effects in trials have generally been mild, most commonly injection-site reactions, but long-term safety data do not exist.

Anyone considering an unapproved peptide should talk with a licensed healthcare professional first. Self-dosing with a research chemical carries risks that no online vendor can assess for you.

The Bottom Line

• SS-31 is not FDA-approved for human use in the United States.
• Elamipretide remains investigational, with a failed Phase 3 trial and a negative advisory committee vote behind it.
• Products sold as SS-31 online are research chemicals, not medicines, and are not reviewed for purity or safety.
• No established human dosing exists, and all dosing information comes from research settings rather than clinical guidance.

COMMON QUESTIONS

Frequently Asked Questions

Has the FDA approved SS-31?

No. SS-31 (elamipretide) is not FDA-approved for any indication, including Barth syndrome and primary mitochondrial myopathy. An FDA advisory committee voted against approval of elamipretide for Barth syndrome in October 2024, and the agency has not authorized the drug since.

Is SS-31 the same as elamipretide?

Yes. SS-31 is the original research name for the peptide whose international nonproprietary name is elamipretide. It has also been studied under the names MTP-131 and Bendavia, and all of these refer to the same molecule.

Can you legally buy SS-31 in the United States?

You cannot buy an FDA-approved SS-31 product because none exists. Peptides sold online are labeled for research use only and are not reviewed by the FDA for purity, sterility, or potency, and importing them for personal medical use is not permitted under federal law. Talk to a licensed healthcare professional before considering any unapproved peptide.