DPP4 and type 2 diabetes mellitus: The classes of antidiabetic drugs used to treat T2D comprise biguanides (such as metformin), dipeptidyl peptidase 4 (DPP-4) inhibitors, sodium-glucose cotransporter 2 (SGLT-2) inhibitors, insulin/insulin analogues, glucagon-like peptide-1 (GLP-1) receptor agonists, sulfonylureas, and thiazolidinediones (10).