GCG and type 2 diabetes mellitus: A range of combination therapy options were available for T2DM such as sulfonylureas, α-glucosidase inhibitors (AGI), thiazolidinediones, dipeptidyl peptidase 4 (DPP-4) inhibitors, glucagon-like peptide 1 (GLP-1) agonists, and sodium-glucose co-transporter 2 (SGLT-2) inhibitors [2].