ALOGLIPTIN IS A SELECTIVE, ORALLY BIOAVAILABLE INHIBITOR OF THE ENZYMATIC ACTIVITY OF DIPEPTIDYL PEPTIDASE-4 (DPP-4). INCREASED CONCENTRATIONS OF THE INCRETIN HORMONES SUCH AS GLUCAGON-LIKE PEPTIDE-1 (GLP-1) AND GLUCOSE-DEPENDENT INSULINOTROPIC POLYPEPTIDE (GIP) ARE RELEASED INTO THE BLOODSTREAM FROM THE SMALL INTESTINE IN RESPONSE TO MEALS. THESE HORMONES CAUSE INSULIN RELEASE FROM THE PANCREATIC BETA CELLS IN A GLUCOSE-DEPENDENT MANNER BUT ARE INACTIVATED BY THE DPP-4 ENZYME WITHIN MINUTES. GLP-1 ALSO LOWERS GLUCAGON SECRETION FROM PANCREATIC ALPHA CELLS, REDUCING HEPATIC GLUCOSE PRODUCTION. IN PATIENTS WITH TYPE 2 DIABETES, CONCENTRATIONS OF GLP-1 ARE REDUCED BUT THE INSULIN RESPONSE TO GLP-1 IS PRESERVED. ALOGLIPTIN IS A DPP-4 INHIBITOR THAT SLOWS THE INACTIVATION OF THE INCRETIN HORMONES, THEREBY INCREASING THEIR BLOODSTREAM CONCENTRATIONS AND REDUCING FASTING AND POSTPRANDIAL GLUCOSE CONCENTRATIONS IN A GLUCOSE-DEPENDENT MANNER IN PATIENTS WITH TYPE 2 DIABETES MELLITUS. ALOGLIPTIN SELECTIVELY BINDS TO AND INHIBITS DPP-4 BUT NOT DPP-8 OR DPP-9 ACTIVITY IN VITRO AT CONCENTRATIONS APPROXIMATING THERAPEUTIC EXPOSURES.