Sitagliptin/metformin fixed-dose combination: in patients with type 2 diabetes mellitus.

Sitagliptin/metformin is a single-tablet, fixed-dose combination of the dipeptidyl peptidase-4 inhibitor sitagliptin and the biguanide antihyperglycaemic metformin that achieves greater improvements in glycaemic control than either component alone in patients with type 2 diabetes mellitus. Recommended dosages of sitagliptin plus metformin, either as the fixed-dose tablet or a combination of the individual agents, significantly reduced glycosylated haemoglobin (HbA(1c)) levels in two well designed clinical trials in treatment-naive patients with type 2 diabetes. The improvements in glycaemic control seen with sitagliptin plus metformin therapy after 18 or 24 weeks were greater than those observed with the individual components alone and/or placebo, and sustained over treatment durations of up to 2 years. As add-on therapy in treatment-experienced patients with inadequate glycaemic control, the HbA(1c)-lowering efficacy of sitagliptin plus metformin was noninferior to that of glimepiride plus metformin in a 30-week, double-blind trial. Sitagliptin plus metformin and glipizide plus metformin lowered HbA(1c) levels by generally similar magnitudes, with the noninferiority of sitagliptin plus metformin to glipizide plus metformin being established in one 52-week study. As part of triple combination therapy, also in treatment-experienced patients with inadequate glycaemic control, sitagliptin added to ongoing glimepiride with or without metformin or ongoing insulin with or without metformin significantly improved glycaemic control over 24 weeks. Sitagliptin plus metformin, as the fixed-dose tablet or a combination of the individual agents, was generally well tolerated in patients with type 2 diabetes, and was associated with a low risk of hypoglycaemia.