Description
SS-31 (elamipretide)
- A synthetic mitochondria-targeted tetrapeptide (alternating aromatic/basic residues), not derived from a natural human peptide like Selank/Semax.
- Mechanism: it selectively concentrates in the inner mitochondrial membrane and binds to cardiolipin, a phospholipid critical for maintaining proper mitochondrial membrane structure and efficient electron transport chain function. This stabilizes the membrane, reduces excess reactive oxygen species (ROS) production, and helps preserve ATP output.
- Primary research focus: mitochondrial dysfunction — conditions like heart failure, ischemia-reperfusion injury, age-related muscle decline, kidney disease, and certain rare mitochondrial/genetic disorders (e.g., Barth syndrome, where it’s had the most clinical traction).
- Route: typically administered subcutaneously or via IV/infusion in clinical trials, unlike the intranasal Selank/Semax.
- Regulatory status: it has gone through several human clinical trials (including for Barth syndrome and geographic atrophy/eye disease) via the company Stealth BioTherapeutics, but as of now it isn’t FDA-approved for any indication in the US — some trials have had mixed or disappointing results on primary endpoints despite promising mechanistic rationale.





