In the initial 26-week, double-blind, double-dummy assessment period of the DURATION-2 trial in patients with Type 2 diabetes on metformin, the once-weekly glucagon-like peptide 1 (GLP-1) receptor agonist exenatide once-weekly resulted in greater HbA1c improvement and weight reduction compared with maximum approved daily doses of sitagliptin or pioglitazone. This evidence concerns the gene GLP1R and type 2 diabetes mellitus.