Dual GIP/GLP-1 receptor agonist with superior weight reduction outcomes vs semaglutide alone.
Binds and neutralises myostatin and related TGF-beta family members. Because myostatin acts as a brake on muscle growth, follistatin is studied for what happens when that signal is reduced. Research context only.
Active ingredient in Mounjaro and Zepbound. SURMOUNT-1 trial showed ~22% average body weight loss — significantly higher than semaglutide's ~15%.
The GIP component may contribute to improved tolerability, with some researchers reporting fewer GI side effects than pure GLP-1 agonists. GIP receptors are also expressed in bone and may have additional metabolic effects.