Efficacy and safety of initial combination therapy with linagliptin and pioglitazone in patients with inadequately controlled type 2 diabetes: a randomized, double-blind, placebo-controlled study

Aims: To compare the efficacy, safety and tolerability of linagliptin or placebo administered for 24 weeks in combination with pioglitazone in patients with type 2 diabetes mellitus (T2DM) exhibiting insufficient glycaemic control (HbA1c 7.5–11.0%). Methods: Patients were randomized to receive the initial combination of 30 mg pioglitazone plus 5 mg linagliptin (n = 259) or pioglitazone plus placebo (n = 130), all once daily. The primary endpoint was change from baseline in HbA1c after 24 weeks of treatment, adjusted for baseline HbA1c and prior antidiabetes medication. Results: After 24 weeks of treatment, the adjusted mean change (±s.e.) in HbA1c with the initial combination of linagliptin plus pioglitazone was −1.06% (±0.06), compared with −0.56% (±0.09) for placebo plus pioglitazone. The difference in adjusted mean HbA1c in the linagliptin group compared with placebo was −0.51% (95% confidence interval [CI] −0.71, −0.30; p < 0.0001). Reductions in fasting plasma glucose (FPG) were significantly greater for linagliptin plus pioglitazone than with placebo plus pioglitazone; −1.8 and −1.0 mmol/l, respectively, equating to a treatment difference of −0.8 mmol/l (95% CI −1.2, −0.4; p < 0.0001). Patients taking linagliptin plus pioglitazone, compared with those receiving placebo plus pioglitazone, were more likely to achieve HbA1c of