GCG and obesity due to melanocortin 4 receptor deficiency: Glucagon-like peptide-1 (GLP-1)is a peptide hormone comprising30 or 31 amino acids.1−3 As an incretin, GLP-1 stimulates a decreasein blood glucose levels and, thus, is of increasing importance withinthe pharmaceutical industry as a therapeutic agent for the treatmentof type 2 diabetes and obesity.4−6 Several GLP-1 analogueshave been produced commercially.7,8 Though currently inwidespread use as an intravenous treatment, challenges remain withregard to its formulation.