SS-31 (elamipretide) dosage: what the trials actually used

The honest way to write about SS-31 dosing is to start with what it is not: there is no approved dose for the things most people are searching for — longevity, energy, recovery, general “mitochondrial support.” Elamipretide (SS-31, formerly MTP-131/Bendavia) is investigational for nearly everything, and its one approval is narrow. So the numbers below are strictly the doses used in human trials for specific diseases, not a regimen anyone should read as a personal protocol. For what the drug actually does — the elegant cardiolipin mechanism and the mostly disappointing clinical record — read the companion SS-31 evidence monograph first; this page is only about the doses.

The dose the modern trials used: 40 mg/day, subcutaneous

Across elamipretide’s later human trials, the regimen was remarkably consistent: 40 mg once daily, injected subcutaneously. The pivotal Phase 3 trial in primary mitochondrial myopathy, MMPOWER-3, randomized 218 adults to 40 mg/day subcutaneous elamipretide or placebo for 24 weeks — and the drug did not beat placebo on the 6-minute walk test or fatigue.^[1] The same 40 mg/day subcutaneous dose was used in the Barth-syndrome crossover trial (TAZPOWER)^[3] and in the dry-AMD ReCLAIM study.^[5] So when a study or a supplier references “the clinical dose,” this is almost always the number they mean.

Where 40 mg came from: the intravenous dose-escalation study

The 40 mg/day figure was not arbitrary. Before the subcutaneous trials, a Phase 1/2 randomized dose-escalation study tested elamipretide as a two-hour intravenous infusion at 0.01, 0.1 and 0.25 mg/kg/hour in adults with primary mitochondrial myopathy.^[2] Only the highest infusion rate produced a walk-distance signal — participants on it walked about 64.5 m farther by day 5, versus 20.4 m on placebo (p = 0.053) — and that signal is what justified moving to a standing daily subcutaneous dose in the larger trials.^[2] It is worth noting the original human dosing was intravenous, not the subcutaneous self-injection that gray-market sellers imply, and the pivotal signal it was built on sat right at the edge of statistical significance.

Barth syndrome: the same dose, and the one approval

In the ultra-rare Barth syndrome, TAZPOWER used 40 mg/day subcutaneous elamipretide against placebo in a 12-week crossover; the blinded portion missed its primary endpoints, but the open-label extension — patients continuing the same daily dose out to about 168 weeks — showed sustained gains in muscle strength and cardiac measures.^[3][4] On that basis the FDA granted accelerated approval to elamipretide, brand name FORZINITY, in September 2025 — given as a once-daily subcutaneous injection for patients with Barth syndrome weighing at least 30 kg, with a confirmatory trial still required.^[6] This is the only context in which elamipretide has an approved dose, and it says nothing about dosing for any other condition.

Dry AMD and heart failure: still investigational

In dry age-related macular degeneration, the small Phase 1 ReCLAIM program also used 40 mg/day subcutaneous elamipretide, reporting mainly that daily self-injection was feasible and tolerable — an early-phase safety-and-feasibility read, not an efficacy dose.^[5] Heart-failure work used single infusions rather than a chronic daily dose. None of this establishes a dose for general or preventive use; these were disease trials with disease endpoints.

The honest bottom line

If you compress it to what the evidence supports: elamipretide was studied at 40 mg once daily, subcutaneously, a dose derived from an intravenous escalation study and carried through the myopathy, Barth, and dry-AMD trials — where it mostly failed to beat placebo, with the lone win being a narrow, confirmation-pending Barth-syndrome approval.^[1][2][6] There is no established dose for healthy people, no evidence it slows aging, and the real-world product is unregulated and injectable. This is not a self-dosing guide. Any legitimate use runs through a clinician and the FORZINITY approval — not a forum protocol. For the mechanism and full trial record see the SS-31 evidence monograph, and for how other mitochondrial peptides are dosed and evidenced, compare MOTS-c dosage and the humanin evidence review.