Latest research on Sitagliptin phosphate

Sitagliptin is a new oral hypoglycemic (anti-diabetic drug) of the new dipeptidyl peptidase-4 (DPP-4) inhibitor class of drugs. This enzyme-inhibiting drug is to be used either alone or in combination with metformin or a thiazolidinedione for control of type 2 diabetes mellitus. The drug works to competitively inhibit a protein/enzyme, dipeptidyl peptidase 4 (DPP-4), that results in an increased amount of active incretins (GLP-1 and GIP), reduced amount of release of glucagon (diminishes its release) and increased release of insulin.

Sitagliptin phosphate dosage

The mice were divided into 5 groups and, orally administered the equally volume of water as vehicle or the DPP-4 inhibitor, sitagliptin (Januvia, Merck & Company, Inc., Rahway, NJ, USA) at the following doses: 0 mg/kg/day; 2.5 mg/kg/day; 5 mg/kg/day; 10 mg/kg/day for 28 days after pump implantation. [source, 2015]
In contrast, Lamont and Drucker treated high fat-fed mice with a remarkably higher dose (2.75 times) of MK-0431 which produced ~90% inhibition of plasma DPP-4 activity and found a significant reduction in glycated hemoglobin observed with DPP-4 inhibition but not with exendin-4 therapy. [source, 2014]
Although the effects of MK-0431 depend on its dose, we were unable to obtain sufficient plasma from mice to measure DPP-4 enzyme activity or active GLP-1 concentration after treatment with MK-0431. [source, 2014]
Hence, we cannot exclude the possibility that higher dose of MK-0431 may have beneficial effects on islet transplantation. [source, 2014]
Per the package insert, “when Januvia is used in combination with a sulfonylurea, a lower dose of sulfonylurea may be required to reduce the risk of hypoglycemia”;1 however, an exact dose reduction is not known nor recommended. [source, 2008]