GLP-1, “GLP-2” & “GLP-3”: What People Really Mean by Semaglutide, Tirzepatide & Retatrutide
Everyone is calling them GLP-1, GLP-2 and GLP-3 — but semaglutide, tirzepatide and retatrutide aren’t three generations of the same drug. Here’s what each one actually targets, why the nicknames caught on, and where investigational retatrutide really stands on the road toward FDA approval.