For laboratory & research use only. Not for human consumption.
Longevity & Cellular Health

Epitalon vs SS-31

Epitalon and SS-31 are KYIN's two Longevity & Cellular Health peptides, and they represent two different dominant theories in cellular aging research — genomic/telomere maintenance versus mitochondrial function preservation — rather than two versions of the same idea.

At a Glance

EpitalonSS-31
CategoryLongevity & Cellular HealthLongevity & Cellular Health
Molecular classSynthetic tetrapeptide (Ala-Glu-Asp-Gly)Synthetic tetrapeptide (D-Arg-Dmt-Lys-Phe), also known as elamipretide
Origin2000s, Vladimir Khavinson, building on 1973 “Epithalamin” pineal-extract researchEarly 2000s, Hazel Szeto & Peter Schiller (discovered while studying opioid receptors)
Primary mechanismTelomerase activity, pineal gland / melatonin signalingBinds cardiolipin at the inner mitochondrial membrane
Primary research focusCellular senescence, telomere biology, aging biomarkersMitochondrial membrane protection, oxidative stress
Human trial dataOne cohort study (266 elderly adults, Khavinson & Morozov 2003)FDA accelerated approval based on the TAZPOWER trial
Regulatory statusNot approved anywhere; sold as a research peptideApproved (as FORZINITY/elamipretide) for Barth syndrome only

How They Differ

Epitalon traces back to 1973, when Soviet researchers described “Epithalamin,” a polypeptide extract from the pineal gland. Vladimir Khavinson synthesized Epitalon — a tetrapeptide matching Epithalamin's amino acid composition — as part of a broader research concept he called “peptide bioregulation,” the idea that a synthetic version of an organ's own short regulatory peptide could be used to study age-related changes in that organ. Epitalon's research program has centered on telomerase activity and the pineal gland's role in aging ever since. See its full discovery history.

SS-31 was discovered by accident: Hazel Szeto and Peter Schiller weren't looking for a mitochondrial compound at all, they were studying opioid receptors, when one of their lead compounds turned out to concentrate heavily inside mitochondria and bind tightly to cardiolipin, a phospholipid found almost exclusively on the inner mitochondrial membrane. That single observation redirected their entire research program toward mitochondrial membrane protection. See its full discovery history, or how it compares to MOTS-c.

Clinical Trial Data

Epitalon: Khavinson and Morozov (2003) followed a cohort of 266 elderly individuals for 6–8 years after receiving short courses of peptide bioregulators, reporting mortality reduction ranging from 1.6× (Epitalon-based regimen alone) up to roughly 4× in the most intensive combined-regimen group, versus untreated controls. This and most other Epitalon research comes from Khavinson's own institute (the St. Petersburg Institute of Bioregulation and Gerontology) and Russian-affiliated journals, and has not been independently replicated in a large Western multi-center trial — it should be read as early domestic cohort evidence, not evidence of the same strength as an FDA-reviewed trial.

SS-31: The TAZPOWER trial studied SS-31 (as elamipretide) in 12 genetically-confirmed Barth syndrome patients, across a 28-week randomized, double-blind, placebo-controlled phase followed by a 168-week open-label extension. The blinded 28-week phase did not reach statistical significance against placebo on its primary endpoints (6-Minute Walk Test and fatigue score); the positive results came from the open-label extension, where knee extensor muscle strength improved more than 45% and 6-Minute Walk Test distance improved by 96.1 meters at week 168 versus the extension's own baseline (p=.003). The FDA's accelerated approval of FORZINITY (elamipretide) in September 2025 was based on this muscle-strength and open-label data, specifically for Barth syndrome — not on the initial blinded trial result.

Why They're Often Studied Together

Epitalon and SS-31 are KYIN's only two Longevity & Cellular Health peptides, and they sit on opposite sides of a real divide in aging biology research: the genomic/telomere theory of aging, which centers on chromosome-end shortening and genetic instability, versus the mitochondrial free-radical theory of aging, which centers on cumulative oxidative damage to mitochondrial membranes and DNA. Studying them together lets researchers compare two largely independent hypotheses about what actually drives cellular aging, rather than two competing approaches to the same target.

Research Use Only Notice This page compares Epitalon and SS-31 for educational and research context only. It is not a claim about current regulatory approval, safety, or legal status in any market. KYIN Peptides sells both compounds strictly for laboratory research use by qualified professionals — not for human or animal use, and not intended for diagnostic, therapeutic, or consumption purposes. The FDA approval referenced above applies to a specific pharmaceutical formulation (FORZINITY) for one rare-disease indication, not to research-grade material sold for laboratory use.
FAQ

Epitalon vs SS-31 questions

Why are Epitalon and SS-31 often discussed together?

Because they're KYIN's only two Longevity & Cellular Health peptides, and they represent two different dominant angles in cellular aging research — telomere and genomic maintenance (Epitalon) versus mitochondrial function preservation (SS-31) — rather than competing versions of the same mechanism.

Has either Epitalon or SS-31 been approved for a specific medical use?

SS-31, under the brand name elamipretide (marketed as FORZINITY), received FDA accelerated approval specifically for Barth syndrome, a rare genetic mitochondrial disorder. Epitalon has never been approved as a drug anywhere; its human data comes from a single Russian institute's own published cohort study, not an FDA-reviewed clinical trial.

Does this comparison mean Epitalon and SS-31 are approved for a particular use?

No. This page compares Epitalon and SS-31 for educational and research context only. Both are sold strictly for laboratory research use and are not evaluated or approved for human or animal use, with the narrow exception noted above of SS-31's specific Barth syndrome drug approval under a different formulation and brand name.

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