P21 vs SS-31 (Elamipretide)

A detailed comparison to help you understand the differences and choose the right peptide for your research goals.

P21

P21 is a synthetic peptide derived from Cerebrolysin, specifically designed to mimic the neurotrophic effects of the parent compound. It promotes neurogenesis and has shown cognitive-enhancing properties in research.

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SS-31 (Elamipretide)

SS-31, also known as Elamipretide or Bendavia, is a mitochondria-targeted tetrapeptide. It has been studied extensively for mitochondrial diseases, heart failure, and age-related decline in mitochondrial function.

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Side-by-Side Comparison

AspectP21SS-31 (Elamipretide)
MechanismInhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity.Concentrates in the inner mitochondrial membrane where it binds to cardiolipin, stabilizing electron transport chain function, reducing reactive oxygen species, and improving ATP production efficiency.
Typical DosageResearch protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks.Clinical trials have used IV infusions of 0.25mg/kg for acute conditions. Subcutaneous dosing protocols for research use typically range from 1-5mg daily.
AdministrationCan be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously.Can be administered IV or subcutaneously. Most clinical research has used IV administration for cardiac conditions.
Side EffectsLimited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue.Generally well-tolerated. Clinical trials reported injection site reactions and occasional headache.
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Key Differences

Unique to P21:

Unique to SS-31 (Elamipretide):

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