← Back to codex

SS-31 (Elamipretide)

Aliases: Elamipretide · Bendavia · MTP-131 · Forzinity

Last verified: 2026-09-23

Approved drugStrong evidencePeptidesMedium interest

The short version

SS-31 (elamipretide) went through a serious development path: phases I–III in mitochondrial myopathies and heart failure, with consistent evidence of cardiolipin targeting and reduced oxidative stress. Results are mixed — parts of the program failed primary endpoints (e.g., in Barth syndrome), parts continue. That is the essence of 'depth': a compound with a real mechanism, real trials, and an undecided outcome.

Identity & type

Molecular type
peptide
Sequence / structure
D-Arg-2′,6′-dimethylTyr-Lys-Phe-NH2
Molecular weight
~640 Da
Origin
Tetrapeptide that accumulates in the inner mitochondrial membrane; developed as elamipretide.

Mechanism of action

Selectively binds cardiolipin, stabilizes cytochrome c and ETC supercomplexes, reduces ROS production and restores mitochondrial dynamics.

Dosing & routes

Official / clinical context

Approved drug — indications, dosing and warnings are defined by the official label. In trials: 4–40 mg/day SC; protocols 5–20 mg/day.

Regulator-approved labeling and published study designs — never a recommendation.

Community-reported practice

In trials: 4–40 mg/day SC; protocols 5–20 mg/day. In Barth patients (approved): improved muscle strength and endurance. The gray-market community reports energy and recovery effects, at a high price.

Unverified self-reports. Not medical advice. Not endorsement.

Expected effects (community)

In Barth patients (approved): improved muscle strength and endurance. The gray-market community reports energy and recovery effects, at a high price.

Protocol — official vs community

Official / label

Elamipretide: no approval. Phase 2/3 studied 40–80 mg SC daily (primary mitochondrial myopathy, Barth syndrome, dry AMD programs).

  1. 01Flat daily dosing in trials

Duration: Trial-defined.

Cardiolipin-binding peptide targeting inner mitochondrial membrane — one of the most-seriously-trialed mitochondrial peptides.

Community (anecdotal)

10–20 mg SC daily (below trial doses, cost-driven).

Cycle:
8–12 weeks.
Break:
4 weeks off.

Trial doses ran far above community ones; under-dosing is the community norm here.

Human evidence

Multiple phase II and one phase III study; primary endpoints not consistently met, secondary signal exists.

Preclinical evidence

The preclinical phase was completed and submitted to regulators as part of registration; pharmacology and toxicology details are part of the official label.

Known risks

  • Mild injection-site reactions; given IV or SCcharacterized
  • Long-term data limited by program durationcharacterized

Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.

Unknowns & evidence gaps

  • Clinical benefit despite mechanistic action

Frequently asked questions

References

  1. Elamipretide program (Stealth BioTherapeutics), phase II/III reports