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ToolsCompareFOXO4-DRI vs Thymalin

FOXO4-DRI vs Thymalin

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

Anti-Aging & Longevity
FOXO4-DRI
Immune SupportAnti-Aging & Longevity
Thymalin
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.
Thymalin is a polypeptide complex isolated from calf thymus glands (developed by the Russian Gerontology Institute), shown to restore immune function, extend lifespan, and reverse thymic involution. Clinical studies demonstrate improved immune parameters and up to 40% reduction in mortality in elderly patients.
Half-Life
Estimated 2-4 hours (D-amino acid confers resistance to proteolysis)
Not well characterized as a complex extract; individual peptides have varying kinetics
Admin Route
Subcutaneous, Intraperitoneal (research)
SubQ, IM
Research
Typical Dose
5 mg/kg in rodent studies; human equivalent approximately 0.5-1 mg/kg
10 mg IM or SC daily
Frequency
3 consecutive days per cycle
Once daily
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
  • Restores thymic function and T-cell immunity
  • Extends healthy lifespan (documented in long-term studies)
  • Reduces infectious disease incidence in elderly
  • Normalizes immune parameters in immunodeficiency
  • Anti-tumor immune surveillance
  • Improves vaccine response in elderly
  • Reduces cardiovascular mortality (40% in landmark Russian study)
  • Normalizes neuroendocrine function
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
  • Very well tolerated in decades of Russian clinical use
  • Mild injection site reactions
  • Rare: mild allergic reaction (natural extract)
  • Transient flu-like symptoms on initiation (immune activation)
Stacks With