For patients who do not achieve control with SRLs, the GH-receptor antagonist Pegvisomant offers a different mechanism of action. Unlike SRLs, which target the tumor, pegvisomant blocks the GH receptor in the liver, preventing the production of IGF-1. This makes it highly effective at normalizing IGF-1 levels in over 90% of patients, even when GH levels remain high. However, because it does not...