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ToolsCompareTestagen vs Thymagen

Testagen vs Thymagen

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

Anti-Aging & Longevity
Testagen
Immune Support
Thymagen
Summary
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.
Thymagen is a dipeptide bioregulator (Glu-Asp) developed by Professor Vladimir Khavinson, tissue-specific for the thymus gland. It supports T-lymphocyte maturation, thymic function, and immune system normalization. As the thymus involutes with age (thymic atrophy), immune competence declines. Thymagen is used to support immune restoration, particularly in aging, post-illness recovery, and immunodeficiency states.
Half-Life
Short (minutes); sustained gene-regulatory effects
Short (minutes); sustained gene-regulatory effects
Admin Route
SubQ, Oral
SubQ, Oral
Research
Typical Dose
10 mg per day
10 mg per day
Frequency
Daily for 10–30 days
Daily for 10–30 days
Key Benefits
  • 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
  • Supports thymic epithelial cell function and T-cell maturation
  • May partially restore thymic output reduced by age-related atrophy
  • Normalizes T-lymphocyte subpopulation balance
  • Supports immune recovery after illness, surgery, or chemotherapy
  • Anti-aging effects on thymic tissue
  • Complementary to Thymosin Alpha-1 and Thymalin in immune protocols
  • May improve vaccine responsiveness in older individuals
Side Effects
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
  • Generally well tolerated
  • Mild injection site reactions
  • No significant immunological adverse events reported
Stacks With