GLP1R and type 2 diabetes mellitus: The first GLP1R agonist approved for clinical use was exenatide (synthetic exendin‐4), a peptide originally isolated from Heloderma suspectum lizard venom by John Eng in 1992.28 Pivotal studies in patients with type 2 diabetes led to the approval of twice daily exenatide which was the first GLP1R agonist in the market in 2005.