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ToolsCompareFollistatin 315 vs Prostamax

Follistatin 315 vs Prostamax

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

Anabolic & IGF
Follistatin 315
Anti-Aging & Longevity
Prostamax
Summary
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.
Prostamax is a tetrapeptide bioregulator (Lys-Glu-Asp-Pro) developed by Professor Vladimir Khavinson, tissue-specific for the prostate gland. It supports prostate epithelial cell function, promotes normalization of prostate tissue, and is studied for its potential in benign prostatic hyperplasia (BPH), prostatitis, and prostate anti-aging. It is one of the more widely used Khavinson bioregulators among men over 40.
Half-Life
~3–5 hours (longer systemic circulation vs FST-344)
Short (minutes); sustained gene-regulatory effects
Admin Route
SubQ, IM
SubQ, Oral
Research
Typical Dose
No established human dosing protocol
10 mg per day
Frequency
Research use only
Daily for 10–30 days
Key Benefits
  • 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
  • Supports normalization of prostate tissue architecture
  • May reduce prostate enlargement associated with BPH
  • Anti-inflammatory effects on prostatic tissue
  • Reduces prostate cell apoptosis from oxidative stress
  • Potential support in chronic prostatitis
  • Anti-aging effects on prostate glandular tissue
  • Complementary to conventional BPH therapies
Side Effects
  • 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
  • Generally well tolerated in available research
  • Mild injection site reactions
  • No significant adverse urological events reported at standard doses
Stacks With