Similar results were obtained in a SURMOUNT-1 DXA substudy (a study of tirzepatide—a dual glucose-dependent insulinotropic polypeptide (GIP)—and GLP-1RAs in participants with obesity or overweight) that demonstrated a large decrease in fat mass (33.9%) and moderate lean mass loss (10.9%) compared to a placebo (2.6%) after 72 weeks [74]. The gene discussed is GIP; the disease is obesity due to melanocortin 4 receptor deficiency.