Efficacy and safety of sitagliptin added to ongoing metformin therapy in patients with type 2 diabetes

ABSTRACT Objective: The purpose of this study was to evaluate the efficacy and safety of sitagliptin as an add-on to metformin therapy in patients with moderately severe (hemoglobin A1c ≥ 8.0% and ≤ 11.0%) type 2 diabetes mellitus (T2DM). Research design and methods: This was a multi­national, randomized, placebo-controlled, parallel-group, double-blind study conducted in 190 patients with T2DM. After ≥ 6 weeks of stable metformin monotherapy (≥ 1500 mg/day), patients were randomized to either the addition of sitagliptin 100 mg once daily or placebo to ongoing metformin for 30 weeks. Main outcome measures: The primary efficacy endpoint was reduction in hemoglobin A1c (HbA1c) measured after 18 weeks of sitagliptin treatment. Key secondary end­points included reduction in fasting plasma glucose (FPG) and 2-hour (2-h) postprandial plasma glucose (PPG) at 18 weeks, and HbA1c at 30 weeks. The proportion of patients meeting the goal of HbA1c