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ToolsCompareFOXO4-DRI vs Testagen

FOXO4-DRI vs Testagen

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

Anti-Aging & Longevity
FOXO4-DRI
Anti-Aging & Longevity
Testagen
Summary
FOXO4-DRI is a D-retro-inverso peptide derived from the FOXO4 protein that selectively induces apoptosis in senescent cells. By disrupting the FOXO4-p53 interaction that keeps senescent cells alive, it triggers programmed cell death specifically in these aging, pro-inflammatory cells while sparing healthy tissue.
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
Estimated 2-4 hours (D-amino acid confers resistance to proteolysis)
Short (minutes); sustained gene-regulatory effects
Admin Route
Subcutaneous, Intraperitoneal (research)
SubQ, Oral
Research
Typical Dose
5 mg/kg in rodent studies; human equivalent approximately 0.5-1 mg/kg
10 mg per day
Frequency
3 consecutive days per cycle
Daily for 10–30 days
Key Benefits
  • Selectively clears senescent cells (senolytics)
  • Reduces senescence-associated secretory phenotype (SASP) and chronic inflammation
  • Demonstrated restoration of physical fitness in aged mice
  • May improve healthspan and reduce age-related tissue dysfunction
  • Potential for treatment of age-related pathologies driven by cellular senescence
  • Does not affect healthy non-senescent cells at therapeutic doses
  • 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
  • Limited human data; largely preclinical evidence
  • Possible temporary inflammatory response as senescent cells are cleared (senolytic effect)
  • Weight loss observed at high doses in rodent studies
  • Unknown long-term safety profile in humans
  • Generally well tolerated
  • Mild injection site reactions
  • No significant endocrine disruption reported at standard doses
Stacks With