Study of Efficacy and Safety of the Dipeptidyl Peptidase-4 Inhibitor Sitagliptin in Patients with Type 2 Diabetes Mellitus

This study aimed to assess the efficacy and safety of dipeptidyl peptidase-4 inhibitor sitagliptin in Japanese patients with type 2 diabetes mellitus. A total of 71 patients aged 33-88 years with a mean baseline hemoglobinA1c (HbA1c) of 8.5％ received sitagliptin 50 mg once daily for 6 months. In this 6-month study, sitagliptin reduced potentially the dose of oral antihyperglycemic drugs, reduced significantly HbA1c levels (difference from baseline －1.2％) with 43.5％ of patients achieving HbA1c levels of < 6.9％. Moreover, sitagliptin had a neutral effect on bodyweight, body mass index and lipid metabolism except for high-density lipoprotein, which decreased significantly, and was generally well tolerated with adverse events being mild in severity.Multiple linear regression analysis indicated that HbA1c, serum creatinine and triglyceride at baseline, and the dose of pioglitazone before the sitagliptin treatment might be predictors of the reduction of HbA1c levels for 6 months.After 6 months of sitagliptin therapy, in 70％ of patients who received the combination therapy of glimepiride and metformin and were greater than or equal to 65 years old and/or serum creatinine levels of 1 mg/dL, the daily dose of glimepiride was decreased under 2 mg/day, which could prevent severe hypoglycemia events.In conclusion, in this study, sitagliptin therapy for 6 months improved glycemic control and was well tolerated with adverse events in Japanese patients with type 2 diabetes.