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ToolsCompareSS-31 (Elamipretide) vs P21

SS-31 (Elamipretide) vs P21

Side-by-side comparison of key properties, dosing, and research.

Anti-Aging & Longevity
SS-31 (Elamipretide)
Cognitive EnhancementAnti-Aging & Longevity
P21
Summary
SS-31 (Elamipretide) is a synthetic mitochondria-targeting tetrapeptide that concentrates in the inner mitochondrial membrane and protects cardiolipin from oxidative damage. It is one of the most promising mitochondrial longevity compounds, studied in clinical trials for heart failure, renal disease, and age-associated mitochondrial dysfunction.
P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
Half-Life
~2–5 hours
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
SubQ
SubQ, Intranasal
Research
Typical Dose
5–10 mg
100–500 mcg
Frequency
Daily to several times per week
Once daily
Key Benefits
  • Restores mitochondrial function and ATP production
  • Protects inner mitochondrial membrane cardiolipin
  • Reduces mitochondrial reactive oxygen species (ROS)
  • Improves exercise capacity and reduces fatigue
  • Cardioprotective — studied in heart failure trials
  • Renoprotective — reduces ischemic kidney injury
  • Anti-aging via mitochondrial preservation
  • Potential in neurodegenerative disease prevention
  • Promotes hippocampal neurogenesis
  • Enhances spatial memory and learning
  • Increases BDNF expression
  • Reduces amyloid-beta plaque formation (animal models)
  • Anti-tau pathology potential
  • Cognitive enhancement without stimulant effects
  • Potential therapeutic for Alzheimer's and cognitive aging
Side Effects
  • Injection site irritation
  • Nausea (rare)
  • Generally well-tolerated in clinical trials
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With