Humanin vs SS-31
Humanin has never been through a randomized human trial; SS-31 has been through several and mostly missed their endpoints. Two different ways of not being proven.
Short answer
SS-31 has FDA approval and humanin does not, which is the main thing separating them. SS-31 suits a reader who puts weight on FDA approval, though that approval does not cover every use it is marketed for, while humanin is marketed for longevity and metabolic health.
Humanin
A genuine cytoprotective mitochondrial-derived peptide whose levels fall with age — but no randomized human trial shows that taking it does anything for people.
Full Humanin evidence reviewSS-31
Elamipretide
A cardiolipin-binding peptide with a mostly disappointing trial history; elamipretide won a narrow, confirmation-pending accelerated FDA approval for Barth syndrome — not for the anti-aging use it's sold for.
Full SS-31 evidence reviewHumanin vs SS-31: head to head
- FDA status / approved use
Humanin
Not approved for any use; sold as an unregulated research injectableSS-31
FDA accelerated approval (Forzinity, 2025) for muscle strength in Barth syndrome only; investigational otherwise- Marketed for
Humanin
Longevity, metabolic healthSS-31
Mitochondrial function, longevity- Outcome areas
Humanin
Longevity / lifespan; Mitochondrial / cellular energySS-31
Mitochondrial / cellular energy; Longevity / lifespan- Evidence grade
Humanin
Preclinical / minimalSS-31
Clinical data- How it works
Humanin
Mitochondrial-derived peptide that blocks cell death in lab and animal studiesSS-31
Binds cardiolipin in the inner mitochondrial membrane, supporting efficient energy production- Route and dosing
Humanin
InjectionSS-31
Subcutaneous injection, 40 mg once daily- Headline human result
Humanin
Not establishedSS-31
No benefit in the phase 3 MMPOWER-3 trial of 218 adults with mitochondrial myopathy; walk distance −3.2 meters vs placebo- Strongest evidence
Humanin
Hashimoto, PNAS 2001. Little or no controlled human outcome data for the marketed useHumanin evidence reviewPubMed 11371646SS-31
Elamipretide (Barth), Genet Med 2024SS-31 evidence reviewPubMed 38602181- Key safety signal
Humanin
Identity, dose, purity and sterility unverified; no long-term human safety dataSS-31
No established dosing or safety profile in healthy users- How it is obtained
Humanin
Sold gray-market as a research chemical; no approved or legitimately compounded human productSS-31
Prescription drug
| Humanin | SS-31 | |
|---|---|---|
| FDA status / approved use | Not approved for any use; sold as an unregulated research injectable | FDA accelerated approval (Forzinity, 2025) for muscle strength in Barth syndrome only; investigational otherwise |
| Marketed for | Longevity, metabolic health | Mitochondrial function, longevity |
| Outcome areas | Longevity / lifespan; Mitochondrial / cellular energy | Mitochondrial / cellular energy; Longevity / lifespan |
| Evidence grade | Preclinical / minimal | Clinical data |
| How it works | Mitochondrial-derived peptide that blocks cell death in lab and animal studies | Binds cardiolipin in the inner mitochondrial membrane, supporting efficient energy production |
| Route and dosing | Injection | Subcutaneous injection, 40 mg once daily |
| Headline human result | Not established | No benefit in the phase 3 MMPOWER-3 trial of 218 adults with mitochondrial myopathy; walk distance −3.2 meters vs placebo |
| Strongest evidence | Hashimoto, PNAS 2001. Little or no controlled human outcome data for the marketed useHumanin evidence reviewPubMed 11371646 | Elamipretide (Barth), Genet Med 2024SS-31 evidence reviewPubMed 38602181 |
| Key safety signal | Identity, dose, purity and sterility unverified; no long-term human safety data | No established dosing or safety profile in healthy users |
| How it is obtained | Sold gray-market as a research chemical; no approved or legitimately compounded human product | Prescription drug |
marks a row where the two differ. “Not established” marks a cell the available evidence does not answer. Evidence grades come from our evidence matrix, which grades each molecule on the human data for the use it is marketed for.
- Clinical data:
- Tested in humans — but investigational, discontinued, or proven only on a surrogate marker (not the marketed outcome).
- Preclinical / minimal:
- Evidence is largely animal, in-vitro, or anecdotal. Little or no controlled human outcome data for the marketed use.
Our verdict
Humanin is preclinical, with cytoprotective and metabolic effects in animals and cell systems and human data that amount to levels declining with age. SS-31 (elamipretide) has the actual clinical record, and it is mostly a record of misses: the Phase 3 MMPOWER-3 in primary mitochondrial myopathy did not meet either primary endpoint, and the TAZPOWER crossover in Barth syndrome missed as well before its open-label extension supported a narrow, confirmation-pending accelerated FDA approval for muscle strength in Barth syndrome. There is no evidence that either benefits healthy people or slows aging, and humanin, along with anything sold as SS-31 outside that approval, is unapproved and investigational material.
Humanin fits if
Humanin suits the reader curious about the first mitochondrial-derived peptide and its cytoprotective biology, with no expectation of a human clinical result.
SS-31 fits if
SS-31 is the one to read if you want to see mitochondrial repair tested in real patients, remembering that its single approval covers Barth syndrome and nothing else.
Humanin vs SS-31: common questions
- Is SS-31 FDA-approved but humanin not?
- Yes. SS-31 has FDA accelerated approval (Forzinity, 2025) for muscle strength in Barth syndrome only; investigational otherwise. Humanin is not approved for any use; sold as an unregulated research injectable.
- Which has stronger human evidence, humanin or SS-31?
- SS-31. It has human clinical data (key source: Elamipretide (Barth), Genet Med 2024), while humanin has only preclinical or minimal evidence (key source: Hashimoto, PNAS 2001).
- What are the main safety concerns with humanin and SS-31?
- For humanin, watch for unverified identity, dose, purity and sterility; no long-term human safety data. SS-31 has no established dosing or safety profile in healthy users.
Key studies behind each
Humanin
- Hashimoto Y, Niikura T, Tajima H, et al. (2001). A rescue factor abolishing neuronal cell death by a wide spectrum of familial Alzheimer's disease genes and Abeta. Proc Natl Acad Sci U S A. PubMed 11371646
- Muzumdar RH, Huffman DM, Atzmon G, et al. (2009). Humanin: a novel central regulator of peripheral insulin action. PLoS One. PubMed 19623253
- Yen K, Mehta HH, Kim SJ, et al. (2020). The mitochondrial derived peptide humanin is a regulator of lifespan and healthspan. Aging (Albany NY). PubMed 32575074
- Lee C, Yen K, Cohen P. (2013). Humanin: a harbinger of mitochondrial-derived peptides? Trends Endocrinol Metab. PubMed 23402768
SS-31
- Szeto HH, Liu S. (2018). Cardiolipin-targeted peptides rejuvenate mitochondrial function, remodel mitochondria, and promote tissue regeneration during aging. Arch Biochem Biophys. PubMed 30359579
- Karaa A, Bertini E, Carelli V, Cohen BH, et al. (2023). Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical Trial. Neurology. PubMed 37268435
- Karaa A, Haas R, Goldstein A, Vockley J, et al. (2018). Randomized dose-escalation trial of elamipretide in adults with primary mitochondrial myopathy. Neurology. PubMed 29500292
- Reid Thompson W, Hornby B, Manuel R, Bradley E, et al. (2021). 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. PubMed 33077895
The full evidence reviews
- Humanin: the first mitochondrial-derived peptide — real biology, no human trials
Discovered in 2001 in a surviving neuron, humanin is a genuine cytoprotective mitochondrial-derived peptide whose levels fall with age — but no randomized human trial shows that taking it does anything for people.
Updated August 2026
- SS-31 peptide (elamipretide): benefits, evidence and approval status
An elegant mitochondrial mechanism meets a hard clinical record: a cardiolipin-binding peptide with a failed myopathy trial and a narrow, confirmation-pending Barth syndrome approval. A straight read.
Updated October 2026