The number of people suffering from diabetes is already over 194 million worldwide and the number is expected to increase by 333 million by 2025. Type II diabetes is also known as non-insulin dependent diabetes and is characterized by a relative disparity between endogenous insulin production and insulin requirements, leading to an elevated glucose. In contrast to Type I diabetes, there is always some endogenous insulin production, and many patients have normal or even elevated blood insulin levels. The disease usually occurs over the age of 40 and treatment involves diet, oral hypoglycemic drugs and exogenous insulin.
However, side effect profile of the given medication, route of administration or difficulties in sustaining glucose control pose serious concerns and necessitate more tolerable treatments that do not cause weight gain and produce less risk of hypoglycemia for patients with type 2 diabetes.
Clinical phase II studies involving Sitagliptin, an investigational diabetes drug, appears to control blood sugar with a low incidence of hypoglycaemia and with a neutral effect on body weight.
Sitagliptin is expected to lower blood glucose levels by increasing the level of active incretin hormones which increase insulin from pancreatic beta-cells and decrease glucagon from pancreatic alpha cells in a glucose-dependent manner (when blood glucose is elevated and not when blood glucose is low). If approved, Sitagliptin would be a member of a new class of antihyperglycaemic agents called DPP-IV inhibitors, which inhibit the DPP-4 enzyme that normally inactivates the incretin gut hormones GLP-1 and GIP.
The patients studied exhibited a safety and tolerability profile similar to placebo. In addition, patients taking Sitagliptin experienced no significant weight gain and a low risk of hypoglycaemia. Patients treated with glipizide had an average weight gain of 1.1 kilogram relative to placebo. Adverse event reports of hypoglycaemia were observed in 4 percent of patients taking Sitagliptin, 17 percent of patients taking glipizide and 2 percent of patients taking placebo.
Results from the studies conducted to date are very promising and ongoing Phase III trials are expected to provide greater insight into the efficacy and tolerability profile of Sitagliptin over a longer period of time.