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ToolsComparePE-22-28 vs ARA-290

PE-22-28 vs ARA-290

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

Cognitive Enhancement
PE-22-28
Immune SupportRecovery & Repair
ARA-290
Summary
PE-22-28 is a synthetic analog of spadin derived from sortilin, designed to block TREK-1 potassium channels with rapid-onset antidepressant and neurogenic effects. It shows fast-acting depression relief (within 24 hours) and promotes hippocampal neurogenesis.
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
Relatively short; CNS effects may persist due to neurogenic mechanisms
~2–4 hours (SC administration)
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
200–400 mcg
4 mg (fixed dose)
Frequency
Once daily
Once daily
Key Benefits
  • Rapid-onset antidepressant effects (within 24 hours)
  • Promotes hippocampal neurogenesis
  • Improves cognitive performance and memory
  • Reduces anxiety and depressive behavior
  • Novel mechanism — does not act on serotonin/dopamine/GABA receptors directly
  • May help treatment-resistant depression
  • Neuroprotective effects
  • 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 models
  • Limited human data available
  • Possible mild headache or transient mood changes at initiation
  • Injection site reactions (SC)
  • Injection site reactions
  • Mild fatigue at initiation
  • Transient warm sensation post-injection
  • Rare: mild headache
Stacks With