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ToolsCompareLarazotide Acetate vs Follistatin 315

Larazotide Acetate vs Follistatin 315

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

Recovery & Repair
Larazotide Acetate
Anabolic & IGF
Follistatin 315
Summary
Larazotide acetate is an 8-amino acid peptide (Gly-Gly-Val-Leu-Val-Gln-Pro-Gly) derived from Zonula Occludens Toxin (ZOT) of Vibrio cholerae. It paradoxically acts as a ZOT antagonist to close tight junctions and reduce intestinal permeability ('leaky gut'). It is the most advanced clinical compound targeting gut permeability directly.
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
Local gut action; minimal systemic exposure
~3–5 hours (longer systemic circulation vs FST-344)
Admin Route
Oral
SubQ, IM
Research
Typical Dose
0.5-2 mg
No established human dosing protocol
Frequency
3x daily
Research use only
Key Benefits
  • Directly reduces intestinal tight junction permeability
  • Clinical efficacy in celiac disease (Phase 3 trials)
  • Reduces systemic inflammation from gut permeability
  • Targets root cause of leaky gut (Zonulin pathway)
  • Local gut action without systemic absorption
  • Potential application in IBS, IBD, autoimmune conditions
  • 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
  • Headache (mild, dose-dependent)
  • Nausea (rare)
  • Well-tolerated overall in clinical trials
  • 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