Initial combination of linagliptin and metformin improves glycaemic control in type 2 diabetes: a randomized, double‐blind, placebo‐controlled study

AIMS: To evaluate the efficacy and safety of initial combination therapy with linagliptin plus metformin versus linagliptin or metformin monotherapy in patients with type 2 diabetes. METHODS: In this 24-week, double-blind, placebo-controlled, Phase III trial, 791 patients were randomized to one of six treatment arms. Two free combination therapy arms received linagliptin 2.5 mg twice daily (bid) + either low (500 mg) or high (1000 mg) dose metformin bid. Four monotherapy arms received linagliptin 5 mg once daily, metformin 500 mg or 1000 mg bid or placebo. Patients with haemoglobin A1c (HbA1c) ≥11.0% were not eligible for randomization and received open-label linagliptin + high-dose metformin. RESULTS: The placebo-corrected mean (95% confidence interval) change in HbA1c from baseline (8.7%) to week 24 was -1.7% (-2.0, -1.4) for linagliptin + high-dose metformin, -1.3% (-1.6, -1.1) for linagliptin + low-dose metformin, -1.2% (-1.5, -0.9) for high-dose metformin, -0.8% (-1.0, -0.5) for low-dose metformin and -0.6 (-0.9, -0.3) for linagliptin (all p < 0.0001). In the open-label arm, the mean change in HbA1c from baseline (11.8%) was -3.7%. Hypoglycaemia occurred at a similar low rate with linagliptin + metformin (1.7%) as with metformin alone (2.4%). Adverse event rates were comparable across treatment arms. No clinically significant changes in body weight were noted. CONCLUSIONS: Initial combination therapy with linagliptin plus metformin was superior to metformin monotherapy in improving glycaemic control, with a similar safety and tolerability profile, no weight gain and a low risk of hypoglycaemia.