SS-31 vs Humanin
Comprehensive side-by-side comparison of mechanisms, dosing, side effects, and research
Also: Elamipretide, Bendavia
SS-31 (sequence D-Arg-Dmt-Lys-Phe-NH2), known generically as elamipretide and sold as FORZINITY, is a synthetic tetrapeptide that homes in on the energy-producing machinery inside your cells. It works by binding cardiolipin, a fat unique to the inner mitochondrial membrane, to help mitochondria run cleaner and make more ATP with less oxidative damage. This is the rare research peptide with a real regulatory finish line: the FDA granted it accelerated approval in September 2025 for Barth syndrome, though it has failed several other major trials.
Also: HN, HNG (S14G-humanin)
Humanin is a 24-amino-acid peptide encoded inside mitochondrial DNA (in the 16S rRNA gene), discovered in 2001 and named for its ability to protect human neurons from Alzheimer-related cell death. It was the first member of the mitochondrial-derived peptide family and is studied mainly for neuroprotection, cell survival, and metabolic and age-related disease. The honest status: it has the deepest preclinical evidence base of any mitochondrial peptide, but human therapeutic trials are essentially absent.
Key Comparison Insights
- SS-31 is FDA approved, while Humanin remains in research stages.
- Both peptides belong to the Anti-Aging category, suggesting similar primary applications.
- SS-31 has stronger research evidence (FDA Approved) compared to Humanin (Animal Studies).
Detailed Comparison
| Attribute | SS-31 | Humanin |
|---|---|---|
| Category | Anti-Aging | Anti-Aging |
| FDA Status | FDA Approved | Not FDA Approved |
| Clinical Status | Pre I II III IV FDA | Pre I II III IV FDA |
| Mechanism of Action | SS-31 is a cell-permeable, mitochondria-targeted peptide that concentrates in the inner mitochondrial membrane and binds tightly to cardiolipin. Cardiolipin is essential for keeping the membrane's folded cristae structure intact and for organizing the proteins of the electron transport chain that generate ATP. By stabilizing cardiolipin, SS-31 helps preserve cristae shape, reduces the electron leakage that produces reactive oxygen species, and supports more efficient ATP production. Studies also suggest it modulates the membrane's surface electrostatics and can limit opening of the mitochondrial permeability transition pore, a trigger for cell death, though the full mechanistic picture is still being worked out. | Humanin is fundamentally a cell-survival signal that blocks apoptosis, the programmed self-destruct cells run when stressed. It binds a trimeric receptor complex made of CNTFR, WSX-1, and gp130 on the cell surface, switching on JAK2/STAT3 survival signaling. Inside the cell it directly grabs the pro-apoptotic protein BAX and stops it from moving to the mitochondria and punching holes in the membrane, which is the step that would otherwise commit the cell to death. It also binds IGFBP-3, modulating IGF-1 signaling and further dialing down apoptosis, and it interacts with formyl peptide receptors. The throughline across all of these is the same: keep stressed cells alive and protect mitochondria. |
| Common Dosing | 40 mg subcutaneous daily Once daily | 5-10 mg weekly divided into 2-3 injections 2-3x weekly (e.g., Monday, Wednesday, Friday) |
| Administration | Subcutaneous injection or IV infusion | Injection (route varies) |
| Typical Duration | Variable by condition | Variable |
| Best Time to Take | Morning | Morning |
Possible Side Effects May vary by individual |
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| Research Summary | Unlike most peptides in this space, SS-31 has been through extensive human trials, with a mixed but consequential record. In TAZPOWER, a randomized placebo-controlled crossover study in Barth syndrome, elamipretide improved skeletal muscle strength and cardiac stroke volume, and the long open-label extension showed sustained benefit, which ultimately supported FDA accelerated approval in September 2025 as the first treatment for that ultra-rare disease. It has also failed prominently: the Phase 3 MMPOWER-3 trial in primary mitochondrial myopathy missed its primary endpoints on the six-minute walk test, the ReCLAIM trial in dry age-related macular degeneration did not hit its primary endpoints, and a heart-failure trial (PROGRESS-HF) also missed its primary endpoint. Across these studies the drug was generally well tolerated, with mostly mild effects such as injection-site reactions, headache and nausea. The accurate summary is that SS-31 is a validated mitochondrial-targeting peptide with one approved indication and a string of negative trials elsewhere, so its benefit appears to depend heavily on the specific disease. | Humanin is one of the best-characterized mitochondrial peptides in the lab, with a large body of in vitro and animal work. It protects neurons against amyloid-beta toxicity, shields retinal pigment epithelium cells from oxidative stress and senescence, and shows protective effects in models of cardiovascular disease and diabetes. Circulating humanin declines with age in humans, and some studies link higher endogenous levels to better metabolic and longevity markers, which fuels the longevity interest. But that is association and animal data, not proof that taking humanin treats any disease. There are no large completed randomized human trials demonstrating clinical benefit, and most of what is sold to consumers is synthetic humanin or analogues like HNG, used far ahead of the evidence. It is a compelling research molecule, not a validated drug. |
Frequently Asked Questions: SS-31 vs Humanin
What is the difference between SS-31 and Humanin?
SS-31 is a anti-aging peptide that ss-31 (sequence d-arg-dmt-lys-phe-nh2), known generically as elamipretide and sold as forzinity, is a synthetic tetrapeptide that homes in on the energy-producing machinery inside your cells. it works by binding cardiolipin, a fat unique to the inner mitochondrial membrane, to help mitochondria run cleaner and make more atp with less oxidative damage. this is the rare research peptide with a real regulatory finish line: the fda granted it accelerated approval in september 2025 for barth syndrome, though it has failed several other major trials. Humanin is a anti-aging peptide that humanin is a 24-amino-acid peptide encoded inside mitochondrial dna (in the 16s rrna gene), discovered in 2001 and named for its ability to protect human neurons from alzheimer-related cell death. it was the first member of the mitochondrial-derived peptide family and is studied mainly for neuroprotection, cell survival, and metabolic and age-related disease. the honest status: it has the deepest preclinical evidence base of any mitochondrial peptide, but human therapeutic trials are essentially absent. The main differences lie in their mechanisms of action and clinical applications.
Which is better, SS-31 or Humanin?
Neither is universally "better" - the choice depends on your specific goals. SS-31 is typically used for anti-aging purposes, while Humanin is used for anti-aging. Always consult with a healthcare provider to determine which may be appropriate for your situation.
Can SS-31 and Humanin be used together?
Some peptide protocols combine multiple compounds for synergistic effects. However, using SS-31 and Humanin together should only be considered under medical supervision, as both compounds have their own side effect profiles and potential interactions. Research on their combined use may be limited.