Below is a transcript of the latest statement (December 2008) published on Diabetes Care about the role of dipeptidyl peptidase four inhibitors in the medical management of hyperglycemia in type 2 diabetes.
Dipeptidyl peptidase four inhibitors.
GLP-1 and glucose-dependent insulinotropic peptide (GIP), the main insulinotropic peptides of intestinal origin (incretins), are rapidly degraded by dipeptidyl peptidase four (DPP-4). DPP-4 is a member of a family of cell membrane proteins that are expressed in many tissues, including immune cells (34). DPP-4 inhibitors are small molecules that enhance the effects of GLP-1 and GIP, increasing glucose-mediated insulin secretion and suppressing glucagon secretion (83,84). The ﬁrst oral DPP-4 inhibitor, sitagliptin, was approved by the Food and Drug Administration in October 2006 for use as monotherapy or in combination with metformin or TZDs.
Another DPP-4 inhibitor, vildagliptin, was approved in Europe in February 2008, and several other compounds are under development. In clinical trials performed to date, DPP-4 inhibitors lower A1Clevels by 0.6–0.9 percentage points and are weight neutral and relatively well tolerated (83,84). They do not cause hypoglycemia when used as monotherapy.
A ﬁxed-dose combination pill with metformin is available. The potential for this class of compounds to interfere with immune function is of concern; an increase in upper respiratory infections has been reported (34).