Follistatin 344

Gene therapy approaches using follistatin have entered early clinical trials for muscular dystrophy. Exogenous peptide injection is unvalidated and commercially available products are suspect.

A rough internal score reflecting quantity, quality, and consistency of human evidence. Not a clinical recommendation.

AAV-follistatin gene therapy trials show safety and modest efficacy in inclusion body myositis. Exogenous injectable follistatin PK data are very limited.

• Myostatin inhibition demonstrated preclinically
• Gene therapy approach shows early promise for myopathies

No validated injectable dosing. Gene therapy uses viral vector delivery, not direct peptide injection.

• Unknown for exogenous injection
• Theoretical cardiac effects from myostatin suppression

Gray-market injectable products are unlikely to contain functional follistatin at claimed doses. Myostatin inhibition may affect cardiac tissue.

Gene therapy evidence does not validate exogenous injection. Product authenticity is a major concern.

• Muscle35