GDF-8 / Myostatin
Mechanism.
GDF-8, commonly known as myostatin, is an endogenous member of the TGF-beta superfamily that acts as a negative regulator of skeletal muscle growth. Rather than being administered as a therapy, the therapeutic interest lies in inhibiting myostatin to promote muscle growth and prevent muscle wasting. Multiple myostatin inhibitors (antibodies and peptides) have been developed and tested in clinical trials for conditions like muscular dystrophy, sarcopenia, and cachexia.
Think of myostatin as the parking brake on your muscles — it's always slightly engaged, limiting how much muscle you can build. Myostatin inhibitors release that brake, allowing muscles to grow more freely. This is why animals with natural myostatin mutations (like Belgian Blue cattle) are extraordinarily muscular.
How it's taken.
Values below describe how GDF-8 / Myostatin has been administered in published trials and labeling. Provided for educational purposes only — this is not medical advice and not instructions for self-administration. Consult your healthcare provider before making any health decision.
Myostatin inhibition approaches include antibodies (domagrozumab, stamulumab), gene therapy, and peptide-based inhibitors. All remain investigational. No commercially available myostatin inhibitor peptide.
Use the free peptide calculator for dilution, unit conversion, and injection volume.
Side effects, rare serious events, who shouldn't.
Every study we cite.
Each study with its published finding and a plain-language note on limitations or funding.