Follistatin 315 vs Dulaglutide
Side-by-side comparison of key properties, dosing, and research.
Anabolic & IGF
Follistatin 315GLP-1 / Weight Loss Agonists
Dulaglutide- 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.
- Dulaglutide (brand name Trulicity) is a once-weekly GLP-1 receptor agonist approved by the FDA for type 2 diabetes management and cardiovascular risk reduction. It consists of two GLP-1 analog chains fused to a modified IgG4 Fc fragment, extending its half-life to approximately 5 days. While primarily a diabetes medication, it produces meaningful weight loss and has established cardiovascular outcomes data from the REWIND trial.
- Half-Life
- ~3–5 hours (longer systemic circulation vs FST-344)
- ~5 days
- Admin Route
- SubQ, IM
- SubQ
- Research
- —
- —
- Typical Dose
- No established human dosing protocol
- 0.75 mg → 1.5 mg
- Frequency
- Research use only
- Once weekly
- 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
- FDA-approved for type 2 diabetes
- Once-weekly subcutaneous dosing via auto-injector pen
- Reduces HbA1c by approximately 1.1–1.6%
- Modest weight loss of 1.5–3 kg at approved doses
- Demonstrated cardiovascular risk reduction (REWIND trial)
- Established long-term safety profile
- Renal protective effects in CKD
- 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
- Nausea (most common, typically transient)
- Diarrhea
- Vomiting
- Decreased appetite
- +3 more
- Stacks With
- —
- —