Epithalon vs SS-31 (Elamipretide)
How Epithalon and SS-31 (Elamipretide) differ on mechanism, dosing, and the strength of the evidence behind each.
How this is graded
Every compound below carries a REGEN research grade, from S (regulatory approval behind the use it is bought for) down to F (no clinical evidence). Ordering follows that grade rather than search volume, so the compound at the top is the one with the most evidence, not the one most often sold. Doses are those reported in published protocols and are not recommendations.
Epithalon
Epithalon (also spelled Epitalon) is a synthetic tetrapeptide with the sequence Ala-Glu-Asp-Gly (AEDG), designed as an analog of epithalamin, a naturally occurring pineal gland peptide. It has been studied — primarily by Russian researchers, notably Vladimir Khavinson's group — in small and preclinical studies for telomerase activation, pineal gland/melatonin regulation, and circadian rhythm effects. It's sold exclusively as a research compound; no FDA approval or large-scale human trial exists.
SS-31 (Elamipretide)
SS-31 (elamipretide) is a small, mitochondria-targeting tetrapeptide that concentrates in the inner mitochondrial membrane and stabilizes cardiolipin, a lipid essential to mitochondrial energy production. It received FDA approval in September 2025 for Barth syndrome, a rare inherited mitochondrial muscle disease, after an extension study showed meaningful improvement in a 6-minute walk test. That approval is genuinely narrow, though: a larger 218-person trial in a different mitochondrial-muscle condition (MMPOWER-3) showed no improvement in walking distance or fatigue, and separate heart-failure and dry-AMD trials both missed their primary endpoints. It's grouped with longevity research because of its mitochondrial mechanism, but that broader case rests mostly on animal data plus this one rare-disease approval.
Evidence compared
| Epithalon | SS-31 (Elamipretide) | |
|---|---|---|
| Research grade | Dgrade | Bgrade |
| Reported dose | 5–10 mg | 40 mg |
| Frequency | daily, 10–20 day cycles | 1x daily |
| Half-life | Expected on the order of minutes (unmodified short peptide) — no direct human plasma half-life study has been published | ~7-10 hours |
| Routes | subcutaneous | subcutaneous |
| Tracked outcomes | — | Muscle Function (mitochondrial disease), Longevity / Mitochondrial Health |
| Contraindications | pregnancy, active malignancy | pregnancy, known hypersensitivity |
Which has more behind it
SS-31 (Elamipretide) carries the stronger evidence grade (B) against Epithalon at D, which means more of what is claimed for SS-31 (Elamipretide) has been tested in humans. Both entries link through to the full reference, where the trial list and citations for each claim are set out in full.
Full Epithalon reference · Full SS-31 (Elamipretide) reference
At a glance
| Compound | Grade | Reported dose | Half-life |
|---|---|---|---|
| Epithalon | Dgrade | 5–10 mg · daily, 10–20 day cycles | Expected on the order of minutes (unmodified short peptide) — no direct human plasma half-life study has been published |
| SS-31 (Elamipretide) | Bgrade | 40 mg · 1x daily | ~7-10 hours |
Frequently asked questions
Epithalon or SS-31 (Elamipretide), which has better evidence?
SS-31 (Elamipretide) carries the stronger evidence grade (B) against Epithalon at D, which means more of what is claimed for SS-31 (Elamipretide) has been tested in humans.
Can Epithalon and SS-31 (Elamipretide) be used together?
The catalog does not list Epithalon and SS-31 (Elamipretide) as a common pairing. Combining compounds does not combine their evidence.
What doses are reported for Epithalon?
Published protocols report 5–10 mg, daily, 10–20 day cycles. This is what the literature describes, not a recommendation.