GLP1R and type 2 diabetes mellitus: Exenatide, a short-acting glucagon-like peptide-1 receptor agonist (GLP1RA), built on the exendin backbone, was the first GLP1RA to receive approval for therapeutic use in people with type 2 diabetes mellitus (T2DM) from the United States Food and Drug Administration (USFDA) in 2005 and from the European Medicines Agency (EMA) in 2006.