SS-31

What it is

SS-31 (also called elamipretide or Bendavia) is a small synthetic peptide that selectively targets and accumulates in mitochondrial inner membranes. It was developed by Stealth BioTherapeutics for various mitochondrial dysfunction-related conditions.

The peptide has been studied in clinical trials for several rare mitochondrial diseases, ischemic injury, and certain cardiovascular conditions. It received regulatory designations including Orphan Drug status for some indications, but has not received broad FDA approval for routine clinical use.

Mechanism of action

SS-31 selectively targets the mitochondrial inner membrane, where it:

• Stabilizes cardiolipin: binds to and protects cardiolipin, a critical inner membrane phospholipid required for proper electron transport chain function
• Improves mitochondrial respiration: supports ATP production efficiency
• Reduces oxidative stress: protects against mitochondrial reactive oxygen species production
• Cell-permeable: the peptide structure allows membrane crossing without requiring receptor-mediated uptake

Clinical evidence

SS-31 has been evaluated in clinical trials for:

• Mitochondrial myopathies (Barth syndrome, primary mitochondrial myopathy)
• Heart failure with preserved ejection fraction
• Ischemia-reperfusion injury
• Age-related macular degeneration
• Renal injury

Results have been mixed. Some indications showed promising signals in early trials but did not meet primary endpoints in larger studies. The compound represents an active area of research with clinical applications still being defined.

Why we don’t prescribe it at The Tide

SS-31 remains in research/development status without clear clinical pathway for the indications relevant to our practice. The compound is complex, expensive, and lacks established protocols for routine clinical use. Patients with mitochondrial dysfunction concerns are typically better served by foundational interventions (exercise, sleep, metabolic optimization, addressing nutritional deficiencies) and potentially MOTS-c in our practice.

Side effects and contraindications

Generally well-tolerated in clinical trials. Side effects include injection site reactions and gastrointestinal effects in some patients. Limited long-term safety data outside trial settings.