What is SS-31?

SS-31 is elamipretide, a mitochondria-targeted tetrapeptide designed to associate with cardiolipin and support mitochondrial inner-membrane function. [1][2][3]

As of September 19, 2025, FDA granted accelerated approval to elamipretide as Forzinity for Barth syndrome, making its regulatory status very different from most research-market mitochondrial peptides. [1][2][3]

That approval does not mean SS-31 is established for general anti-aging, athletic recovery, dry AMD, heart failure, or mitochondrial-wellness use. [1][2][3]

What SS-31 is investigated for

SS-31 evidence is grouped by practical use case and injectable route context. Each use case separates confidence, human evidence, animal or mechanistic support, and the practical takeaway.

Barth syndrome

Injectable

80% Strong

Barth syndrome has the clearest clinical-development evidence for SS-31/elamipretide. [1][2][4]

Human evidence

Randomized and long-term extension data evaluate elamipretide in Barth syndrome. [1][2][4]

Animal / mechanistic evidence

Tafazzin knockdown mouse work supports the Barth mitochondrial mechanism. [3][5]

Primary mitochondrial myopathy and fatigue

Injectable

58% Emerging

Primary mitochondrial myopathy is human-studied but not as strong as the Barth syndrome evidence. [10][11]

Human evidence

MMPOWER-3 tested elamipretide in primary mitochondrial myopathy, with efficacy and safety results that require cautious interpretation. [10][11]

Animal / mechanistic evidence

Mechanistic reviews connect elamipretide to cardiolipin and mitochondrial bioenergetics. [10][11]

Mitochondrial function and cellular energy

Injectable

54% Emerging

Cellular-energy claims depend on mitochondrial disease biology, not broad wellness or anti-aging proof. [11][3][5]

Human evidence

Human mitochondrial-disease studies support the cellular-energy discussion indirectly through disease-specific endpoints. [10][11]

Animal / mechanistic evidence

Mechanism and tafazzin-model studies support mitochondrial morphology, mitophagy, and bioenergetic plausibility. [11][3][5]

Heart-failure mitochondrial function

Injectable

30% Limited

Heart-failure support is a separate preclinical mitochondrial-function signal. [25][11]

Human evidence

Human heart-failure outcome evidence is not established in the cited literature. [25][11]

Animal / mechanistic evidence

A dog model of advanced heart failure reported improved left-ventricular and mitochondrial function after chronic elamipretide therapy. [25][11]

Mitochondrial aging biology

Injectable

24% Limited

Mitochondrial aging biology is a plausible mechanism bucket, not evidence of human anti-aging benefit. [11][5]

Human evidence

Human anti-aging, longevity, or broad wellness outcomes are not established for SS-31/elamipretide. [10][11]

Animal / mechanistic evidence

Mechanistic reviews connect elamipretide to cardiolipin, mitochondrial bioenergetics, morphology, and stress adaptation, which explains the mitochondrial-aging rationale. [11][5]

Evidence snapshot

Overall confidence

Strong

80%

Elamipretide has strong disease-specific support for Barth syndrome. General mitochondrial wellness, fatigue, or anti-aging uses are much less settled. [1][2][3]

Overall confidence is a page-level composite, not an average; it weighs evidence quality, route/molecule match, and practical limitations.

80%

Human evidence

Strong

FORZINITY labeling supports elamipretide for improving muscle strength in Barth syndrome under accelerated approval. Broader mitochondrial uses do not inherit that confidence. [1][2][3]

34%

Animal / preclinical

Limited

Cardiolipin and mitochondrial-membrane evidence directly support the Barth-syndrome rationale. [1][2][3]

80%

Mechanism support

Strong

Elamipretide is designed to interact with cardiolipin, a phospholipid important for mitochondrial inner-membrane structure and respiratory-chain function. The mechanism aims to stabilize mitochondrial energy machinery under stress. [1][2][3]

Forms & administration

SS-31 is tracked as injectable elamipretide. The approved Forzinity Barth-syndrome label is separate from broader SS-31 mitochondrial wellness discussions. [6][7][1]

Injectable

Dosing & protocols

The notes below separate published trial design from commonly discussed cosmetic or compounded-use patterns. They are educational context only, not a prescription or product instruction.

Typical Range

Forzinity labeling uses 40 mg subcutaneously once daily for Barth syndrome patients weighing at least 30 kg. Common non-label SS-31 protocols list 0.5-1.5 mg/kg daily and belong to a separate context. [12][6][7][1]

Frequency

Forzinity labeling uses once-daily dosing at the same time each day; common non-label calendars also use daily entries. [12][6][7][1]

Timing Considerations

Morning timing is the common non-label anchor; Forzinity labeling emphasizes the same time each day rather than a meal or workout anchor. [12][6][7][1]

Cycle Length

Common non-label SS-31 blocks run 4-12 weeks. Barth-syndrome treatment follows the prescription label and disease-specific follow-up. [12][6][7][1]

What to expect

Weeks 4-12

Injectable elamipretide outcomes in mitochondrial-disease contexts center on muscle strength, fatigue, walking capacity, and daily function. [1][2][3][12][6][7]

Months

Injectable Barth-syndrome treatment may show gradual changes in disease-specific function, biomarkers, and confirmed strength outcomes. [1][2][3][12][6][7]

After stopping

Mitochondrial-disease benefits may lessen after injectable elamipretide ends if the underlying disease process remains active. [1][2][3][12][6][7]

Safety profile

SS-31 safety now includes Forzinity label data for Barth syndrome and a separate non-label mitochondrial-wellness context. [12][6][1]

Common side effects

Injection-site reactions [12][6][1]
Skin rash [12][6][1]
Eosinophil increase [12][6][1]

Cautions

Serious hypersensitivity [12][6][1]
Benzyl alcohol / neonates [12][6][1]
Renal impairment [12][6][1]
Non-label use [12][6][1]

What we don't know

Barth-syndrome label data do not settle safety for non-label mitochondrial wellness use, different doses, or unsupervised compounded products. [12][6][1]

Who SS-31 is not for

Route-specific avoid and medical-review notes:

Use outside label without clinician oversight
Use outside label without clinician oversight warrants medical review or avoidance for SS-31. [6][1][2][3]
Pregnancy or breastfeeding unless specifically supervised
Pregnancy or breastfeeding unless specifically supervised warrants medical review or avoidance for SS-31. [6][1][2][3]

Drug & supplement interactions

Documented interactions are separated from theoretical or route-specific cautions.

Theoretical interactions

Mitochondrial stacks
CoQ10, NAD+ products, MOTS-c, or other mitochondrial supplements can blur fatigue, exercise, and symptom tracking; this is a mechanism-and-dose gap. [12][6][1]
Renal-stress drugs
Nephrotoxic drugs or unstable renal medication regimens can make renal status and elamipretide tolerability harder to separate; this is a route-specific caution. [12][6][1]
Allergy-treatment overlap
Antihistamines or corticosteroids can mask mild rash or hypersensitivity signals during early dosing; this is a route-specific caution. [12][6][1]

Regulatory status

United States

In the U.S. as of 2026-06-21, FORZINITY elamipretide has FDA accelerated approval for Barth syndrome only. Mitochondrial wellness, anti-aging, or compounded SS-31 use sits outside that label and should not be treated as FDA-approved. [12][6][7][8][14]

Route	FDA drug approval	503A compounding
Injectable	Approved FORZINITY elamipretide is FDA-approved under accelerated approval for Barth syndrome; mitochondrial wellness, anti-aging, or compounded SS-31 use is outside that label. [12][6][7][7]	Not Listed 503A compounding for SS-31 is separate from FDA-approved product labeling; a compounded preparation is not the approved product and is not FDA-approved. [12][6][7][7][8][14][15]

Injectable

FDA drug approval

Approved

FORZINITY elamipretide is FDA-approved under accelerated approval for Barth syndrome; mitochondrial wellness, anti-aging, or compounded SS-31 use is outside that label. [12][6][7][7]

503A compounding

Not Listed

503A compounding for SS-31 is separate from FDA-approved product labeling; a compounded preparation is not the approved product and is not FDA-approved. [12][6][7][7][8][14][15]

International

EU/Europe, UK, Canada, and Australia require product-specific checks in EMA/MHRA, Health Canada, and TGA registers. A U.S. FDA approval does not automatically establish the same approved indication, route, or product status in those markets. [17][18][19][20]

Sports & competition

WADA does not list SS-31 here as S2 in the same way as GH or gonadotropins, but non-approved systemic, wellness, or compounded use can still require S0-style anti-doping review. [9][7][8][14][15]

How it works

SS-31, now approved as elamipretide for Barth syndrome, is designed to interact with cardiolipin in the mitochondrial inner membrane. In practical terms, the mechanism aims to stabilize respiratory-chain structure and energy production under mitochondrial stress. [1][2][3]

Injectable delivery and disease context define the claim. The pathway is most meaningful in cardiolipin-related mitochondrial disease biology; it does not automatically translate into broad anti-aging, fatigue, athletic, or wellness benefits without indication-specific outcomes. The route and diagnosis narrow what the mitochondrial mechanism can reasonably imply. [1][2][3]

Research gaps & open questions

What the current literature has not yet settled about SS-31:

A key evidence gap is confirmatory Barth syndrome outcomes after accelerated approval. [1][2][3]

A key evidence gap is indication-specific evidence for dry AMD, myopathy, and heart failure. [1][2][3]

A key evidence gap is safety and usefulness outside rare-disease care. [1][2][3]

Common questions

Is SS-31 FDA-approved?

Yes. FDA granted accelerated approval to FORZINITY elamipretide for Barth syndrome; that does not approve general mitochondrial wellness or anti-aging use. [7][8][6][1]

Is SS-31 approved for anti-aging?

No. SS-31 is not FDA-approved for anti-aging; the U.S. approval and human outcomes are disease-specific for Barth syndrome. [7][8][6][1]

Is elamipretide the same as SS-31?

Yes. Elamipretide is the drug name associated with SS-31; approved use is indication-specific, not a blanket mitochondrial wellness claim. [7][8][6][1]

Myths & misconceptions

Myth

FDA approval means SS-31 is proven for all mitochondrial goals.

Reality

Approval is for a specific disease setting and cannot be generalized automatically. [1][2][3]

Myth

Mitochondrial support equals longevity benefit.

Reality

Mitochondrial mechanism is not the same as proven lifespan or anti-aging outcome. [1][2][3]

History & discovery

SS-31, later developed as elamipretide, began as a mitochondria-targeted peptide aimed at cardiolipin and inner-membrane stress biology. Barth syndrome eventually became the clearest clinical path. That distinction keeps the origin story tied to evidence strength, route, and product identity rather than broad clinical certainty. [1][2][3][6][12]

Clinical trials and long-term extension data tied elamipretide to Barth syndrome, a cardiolipin-related mitochondrial disease. That moved SS-31 from broad mitochondrial interest into a defined indication. [1][2][3][6][12]

FDA accelerated approval for FORZINITY made the history disease-specific: approved elamipretide is a Barth syndrome therapy, not a blanket mitochondrial wellness or anti-aging product. [1][2][3][6][12]

Published research 9 studies

[1]

Long-term efficacy and safety of elamipretide in patients with Barth syndrome: 168-week open-label extension results of TAZPOWER.

Genet Med, 2024 Jul. human clinical.

[2]

A phase 2/3 randomized clinical trial followed by an open-label extension to evaluate the effectiveness of elamipretide in Barth syndrome, a genetic disorder of mitochondrial cardiolipin metabolism.

Genet Med, 2021 Mar. human clinical.

[3]

Beneficial effects of SS-31 peptide on cardiac mitochondrial dysfunction in tafazzin knockdown mice.

Sci Rep, 2022 Nov 18. animal.

[4]

Elamipretide in the Management of Barth Syndrome: Current Evidence and a Case Report.

Mol Genet Metab, 2025 Sep-Oct. review.

[5]

SS-31 treatment ameliorates cardiac mitochondrial morphology and defective mitophagy in a murine model of Barth syndrome.

Sci Rep, 2024 Jun 13. animal.

[6]

FDA grants accelerated approval to elamipretide for Barth syndrome

U.S. Food and Drug Administration, 2025-09-19. regulatory.

[7]

Drugs@FDA/openFDA query for SS-31

U.S. Food and Drug Administration. database query.

[8]

Compounding and the FDA: Questions and Answers

U.S. Food and Drug Administration. official guidance.

[9]

The 2026 List of Prohibited Substances and Methods

World Anti-Doping Agency. regulatory.