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ToolsCompareFOXO4-DRI vs P21

FOXO4-DRI vs P21

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

Anti-Aging & Longevity
FOXO4-DRI
Cognitive EnhancementAnti-Aging & Longevity
P21
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.
P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
Half-Life
Estimated 2-4 hours (D-amino acid confers resistance to proteolysis)
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
Subcutaneous, Intraperitoneal (research)
SubQ, Intranasal
Research
Typical Dose
5 mg/kg in rodent studies; human equivalent approximately 0.5-1 mg/kg
100–500 mcg
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
  • Promotes hippocampal neurogenesis
  • Enhances spatial memory and learning
  • Increases BDNF expression
  • Reduces amyloid-beta plaque formation (animal models)
  • Anti-tau pathology potential
  • Cognitive enhancement without stimulant effects
  • Potential therapeutic for Alzheimer's and cognitive aging
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 in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With