Dipeptidyl peptidase-4 (DPP-4)

Class

DPP-4 (dipeptidyl peptidase-4) inhibitor

Pathway

Incretin pathway — DPP-4 inhibition prolongs active GLP-1/GIP levels, enhancing glucose-dependent insulin secretion

Dipeptidyl peptidase-4 (DPP-4) is an enzyme present on cell surfaces throughout the body and in circulating form in blood, where it rapidly breaks down incretin hormones, chiefly glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). These hormones are released from the gut after eating and act on the pancreas to promote insulin release in proportion to blood glucose levels, while also suppressing glucagon, a hormone that raises glucose. Because DPP-4 degrades these incretins within minutes of their release, inhibiting the enzyme extends their activity, amplifying the body's own glucose-dependent insulin response rather than forcing insulin release irrespective of blood sugar. This mechanism is central to managing type 2 diabetes, a condition characterized by impaired insulin secretion and reduced incretin effect. Because insulin release remains tied to actual glucose concentration, this approach carries a comparatively low risk of driving blood sugar too low, a limitation of some older insulin-secretagogue drug classes. DPP-4 inhibitors are typically oral small molecules taken once or twice daily, valued for their tolerability and ease of combination with other glucose-lowering agents, addressing an important need in a disease affecting glucose regulation across multiple organ systems.