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ToolsCompareFOXO4-DRI vs Thymulin

FOXO4-DRI vs Thymulin

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

Anti-Aging & Longevity
FOXO4-DRI
Immune Support
Thymulin
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.
Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
Half-Life
Estimated 2-4 hours (D-amino acid confers resistance to proteolysis)
~30 minutes active half-life
Admin Route
Subcutaneous, Intraperitoneal (research)
SubQ
Research
Typical Dose
5 mg/kg in rodent studies; human equivalent approximately 0.5-1 mg/kg
20-30 mcg
Frequency
3 consecutive days per cycle
10 days per month (Khavinson protocol)
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
  • Enhances T-cell maturation and differentiation
  • Boosts NK cell cytotoxic activity
  • Reduces inflammatory cytokine production (TNF-α, IL-1)
  • Anti-nociceptive (pain-reducing) properties
  • Restores age-related immune decline
  • Anti-inflammatory via serotonin pathway modulation
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
  • Injection site reactions
  • Mild fatigue initially as immune system activates
Stacks With