Tesamorelin vs Follistatin 315
Side-by-side comparison of key properties, dosing, and research.
Growth Hormone PeptidesFat Loss & Metabolic
TesamorelinAnabolic & IGF
Follistatin 315- Summary
- Tesamorelin is an FDA-approved synthetic GHRH analog specifically indicated for reduction of excess abdominal (visceral) fat in HIV patients with lipodystrophy. It is the only GHRH peptide with FDA approval for a fat-reduction indication and is studied off-label for metabolic syndrome and cognitive function.
- 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
- ~26 minutes
- ~3–5 hours (longer systemic circulation vs FST-344)
- Admin Route
- SubQ
- SubQ, IM
- Research
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- Typical Dose
- 2 mg
- No established human dosing protocol
- Frequency
- Once daily
- Research use only
- Key Benefits
- FDA-approved for visceral fat reduction in HIV lipodystrophy
- Significant reduction in trunk/visceral fat (average 15–20% in trials)
- Improved triglyceride and lipid profiles
- Potential cognitive benefits and memory improvement
- Preserves lean mass while reducing fat
- Natural pulsatile GH stimulation
- 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
- Injection site reactions (redness, irritation)
- Arthralgia and joint pain
- Peripheral edema
- Carpal tunnel syndrome
- +2 more
- 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
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