INS and obesity due to melanocortin 4 receptor deficiency: In a study that included individuals with obesity and prediabetes, the GLP-1RA liraglutide improved insulin sensitivity measured by HOMA–IR for insulin resistance (HOMA-IR) (Homeostatic Model Assessment for Insulin Resistance) as early as 2 weeks prior to weight loss as well as decreasing insulin, C-peptide, and fasting glucagon levels [92].