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ToolsCompareFOXO4-DRI vs Follistatin 315

FOXO4-DRI vs Follistatin 315

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

Anti-Aging & Longevity
FOXO4-DRI
Anabolic & IGF
Follistatin 315
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.
Follistatin 315 is a splice variant isoform of follistatin produced by alternative mRNA processing. Unlike Follistatin 344 which is tethered to cell surfaces via heparan sulfate proteoglycans, FST-315 circulates freely in the bloodstream and has broader systemic distribution. It is the predominant circulating form and exerts systemic myostatin inhibition as well as FSH suppression, making it relevant to both muscle growth and reproductive endocrinology.
Half-Life
Estimated 2-4 hours (D-amino acid confers resistance to proteolysis)
~3–5 hours (longer systemic circulation vs FST-344)
Admin Route
Subcutaneous, Intraperitoneal (research)
SubQ, IM
Research
Typical Dose
5 mg/kg in rodent studies; human equivalent approximately 0.5-1 mg/kg
No established human dosing protocol
Frequency
3 consecutive days per cycle
Research use only
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
  • Systemic myostatin inhibition for whole-body muscle growth
  • Freely circulating — broader tissue distribution than FST-344
  • Strong FSH-suppressive activity useful in certain hormonal protocols
  • Potential for greater anabolic effect across multiple muscle groups simultaneously
  • May be more relevant to reproductive endocrinology applications
  • Studied in gene therapy approaches for muscular dystrophy
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
  • Systemic FSH suppression — significant concern for fertility
  • Greater potential for off-target effects vs FST-344 due to systemic distribution
  • Limited human safety data
  • Potential cardiac hypertrophy with prolonged high-dose exposure
Stacks With