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ToolsCompareThymosin Alpha-1 vs Testagen

Thymosin Alpha-1 vs Testagen

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

Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1
Anti-Aging & Longevity
Testagen
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.
Testagen is a tetrapeptide bioregulator (Lys-Glu-Asp-Gly) developed by Professor Vladimir Khavinson, tissue-specific for the testes. It supports Leydig cell function, normalization of testosterone biosynthesis, and spermatogenic activity. Testagen is used in men's health protocols for age-related testosterone decline, male fertility support, and testicular anti-aging.
Half-Life
2–3 hours
Short (minutes); sustained gene-regulatory effects
Admin Route
SubQ
SubQ, Oral
Research
Typical Dose
0.8–1.6 mg
10 mg per day
Frequency
Twice weekly
Daily for 10–30 days
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
  • Supports endogenous testosterone synthesis via Leydig cell normalization
  • Promotes spermatogenesis and sperm quality
  • Anti-aging effects on testicular tissue
  • May attenuate age-related testosterone decline
  • Mechanistically distinct from TRT — does not suppress HPG axis
  • Useful adjunct to Gonadorelin and Kisspeptin-10 in male hormonal protocols
  • Supports male fertility without exogenous hormone replacement
Side Effects
  • Injection site irritation
  • Mild flu-like symptoms initially (immune activation)
  • Fatigue (rare)
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
Stacks With