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ToolsCompareP21 vs ARA-290

P21 vs ARA-290

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Immune SupportRecovery & Repair
ARA-290
Summary
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.
ARA-290 is a synthetic 11-amino acid peptide derived from the helix B region of erythropoietin (EPO). Unlike EPO, it selectively activates the innate repair receptor (IRR) without stimulating hematopoiesis, providing tissue protection, anti-inflammation, and neuropathy relief.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
~2–4 hours (SC administration)
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
100–500 mcg
4 mg (fixed dose)
Frequency
Once daily
Once daily
Key Benefits
  • 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
  • Reduces neuropathic pain from small fiber neuropathy
  • Anti-inflammatory without immune suppression
  • Tissue protection after ischemia/reperfusion injury
  • Promotes nerve fiber regeneration
  • Improves symptoms of sarcoidosis-associated neuropathy
  • May reduce insulin resistance and improve metabolic health
  • Shown to improve autonomic neuropathy symptoms
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Injection site reactions
  • Mild fatigue at initiation
  • Transient warm sensation post-injection
  • Rare: mild headache
Stacks With