DPP4 and type 2 diabetes mellitus: Currently, clinically available drugs for T2DM, including sulfonylureas, glucagon‐like peptide‐1 (GLP‐1) agonists, sodium‐glucose transport protein 2 (SGLT2) inhibitors, peroxisome proliferator‐activated receptor gamma (PPARγ) agonists, dipeptidyl‐peptidase 4 (DPP4) inhibitors and biguanides, control blood glucose levels by acting on peripheral insulin target tissues, such as pancreas, intestine, muscle and liver.1, 2