New — Free Peptide Starter Guide (2026): 13 chapters, 34 cited studies

Get it free
ToolsCompareThymosin Alpha-1 vs PE-22-28

Thymosin Alpha-1 vs PE-22-28

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

Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1
Cognitive Enhancement
PE-22-28
Summary
Thymosin Alpha-1 is a naturally occurring 28-amino acid peptide derived from the thymus gland. It is a powerful immune modulator approved in many countries for treating chronic hepatitis B, hepatitis C, and as an adjunct in cancer immunotherapy.
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.
Half-Life
2–3 hours
Relatively short; CNS effects may persist due to neurogenic mechanisms
Admin Route
SubQ
SubQ, Intranasal
Research
Typical Dose
0.8–1.6 mg
200–400 mcg
Frequency
Twice weekly
Once daily
Key Benefits
  • Enhances T-cell and NK cell activity
  • Supports recovery from viral and bacterial infections
  • May reduce inflammation systemically
  • Supports healthy aging and immune resilience
  • Improves vaccine response
  • Supports liver health
  • May help with chronic fatigue syndrome and post-viral conditions
  • Approved in multiple countries for hepatitis B and C treatment
  • 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
Side Effects
  • Injection site irritation
  • Mild flu-like symptoms initially (immune activation)
  • Fatigue (rare)
  • Generally well tolerated in animal models
  • Limited human data available
  • Possible mild headache or transient mood changes at initiation
  • Injection site reactions (SC)
Stacks With