Dobs AS et al. – In patients with type 2 diabetes, the addition of sitagliptin for 54 weeks to ongoing therapy with metformin and rosiglitazone improved glycemic control and was generally well tolerated compared with placebo.

• This was a randomized, double-blind, placebo-controlled, parallel-group, 54-week study conducted at 41 sites in North and South America, Europe, and Asia in 278 patients with hemoglobin A1c (A1C) ≥7.5% to ≤11.0% despite ongoing combination therapy with metformin (≥1500 mg/d) and rosiglitazone (≥4 mg/d).
• Patients were randomized (2:1) to receive sitagliptin 100 mg or placebo once daily. The main outcome measure was change from baseline in A1C at Week 18.

• Mean baseline A1C was 8.8%.
• The mean placebo-adjusted change from baseline in A1C with sitagliptin treatment was –0.7% (P<0.001) at Week 18 and -0.8% (P<0.001) at Week 54.
• There were significant (P<0.001) reductions also in 2-hour postmeal glucose and fasting plasma glucose compared with placebo at Weeks 18 and 54.
• Significantly higher proportions of sitagliptin-treated than placebo-treated patients had A1C <7.0% at Weeks 18 (22% versus 9%; P=0.003) and 54 (26% versus 14%; P=0.015).
• Changes in body weight and rates of adverse events overall, hypoglycemia, and gastrointestinal adverse events were similar in the sitagliptin and placebo groups during the 54-week study.