SS-31 (elamipretide, Bendavia) is a small synthetic peptide that selectively concentrates in the inner mitochondrial membrane.

Mechanism — Binds cardiolipin, the signature phospholipid of the inner mitochondrial membrane. Stabilizes cristae structure, preserves electron transport chain organization, reduces ROS leak, and restores ATP synthesis in dysfunctional mitochondria.

Use case — Investigational for heart failure, primary mitochondrial diseases, age-related macular degeneration, and recovery from ischemic injury. Research dosing 40 mg subcutaneous daily.

Caveats — Investigational. Phase III trials have had mixed results. Promising mechanism, real but modest effect sizes.