Follistatin-344 — the myostatin inhibitor.

Follistatin-344 is a glycoprotein that binds and neutralises myostatin (GDF-8) — the body’s natural brake on muscle growth. It is among the most powerful muscle-growth research compounds and one of the most expensive on PeptideCompare.

Last reviewed: 2026-06-24

What is Follistatin-344?

Follistatin is a naturally occurring protein that binds members of the TGF-beta family, most notably myostatin. Myostatin limits muscle growth; inhibiting it allows greater muscle development — demonstrated dramatically in "double-muscled" animals with myostatin mutations. Follistatin-344 is one isoform studied for this effect. It is a large, complex molecule, which is reflected in its high price.

What does the research show?

EVIDENCE SUMMARY

STRONG

Muscle growth (animal) — Robust animal data: myostatin inhibition produces significant muscle hypertrophy. Gene-therapy studies show dramatic effects.

MODERATE

Muscular dystrophy research — Follistatin gene therapy studied in muscular dystrophy with encouraging early results.

LIMITED

Injectable peptide efficacy — Whether injected follistatin protein achieves the same effect as genetic overexpression is unclear. Short half-life is a limitation.

⚠ Most dramatic results come from gene therapy, not injectable protein. Injectable follistatin efficacy and half-life are limiting factors rarely acknowledged in marketing. High cost and limited EU availability. This is a research compound, not a medication.

What to look for when buying in Europe

Expensive and carried by few EU vendors — PeptideCompare currently tracks limited suppliers. At this price, COA verification is essential. Require ≥98% purity with mass-spec and be cautious of cheap offers.

✓ PeptideCompare tracks Follistatin-344 from 1 COA-verified EU vendors, starting from €129.00. The gap between the cheapest and priciest vendor is large; compare first.

Compare Follistatin-344 across EU suppliers

1 EU vendors · COA-verified · from €129.00 · Updated monthly

Follistatin-344 — the myostatin inhibitor.

What is Follistatin-344?

What does the research show?

What to look for when buying in Europe

Compare Follistatin-344 across EU suppliers

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