Efficacy and safety of linagliptin in type 2 diabetes subjects at high risk for renal and cardiovascular disease: a pooled analysis of six phase III clinical trials

BACKGROUND: In patients with type 2 diabetes mellitus (T2DM), hypertension and microalbuminuria are predictive markers for increased renal and cardiovascular risk. This post hoc analysis of data from a global development program aimed to evaluate the efficacy and safety of linagliptin in a population with joint prevalence of these two vascular risk factors. METHODS: Data for patients with baseline microalbuminuria (urine albumin-to-creatinine ratio 30-300 mg/g) and hypertension (systolic blood pressure ≥ 140 mm Hg and/or diastolic blood pressure ≥ 90 mm Hg and/or a history of hypertension; and/or an antihypertensive treatment at baseline) who participated in any of six randomized, placebo-controlled, phase III trials were analyzed. Participants received linagliptin 5 mg daily (alone or in combination with other oral antidiabetic drugs) or placebo for 18 to 24 weeks. RESULTS: Of 3,119 patients, 512 had both microalbuminuria and hypertension (linagliptin, 366; placebo, 146). Baseline mean (SD) HbA1c was 8.3 (0.9)% and 8.4 (0.9)%; median (range) urine albumin-to-creatinine ratio was 60 (30-292) mg/g and 64 (30-298) mg/g; mean (SD) systolic blood pressure was 138 (15) mm Hg and 135 (16) mm Hg; and mean (SD) diastolic blood pressure was 81 (10) mm Hg and 81 (10) mm Hg, for linagliptin and placebo, respectively. Placebo-corrected mean change in HbA1c from baseline to week 18 and week 24 was -0.57% (95% CI: -0.75, -0.39; P < 0.0001) and -0.59% (95% CI: -0.80, -0.39; P < 0.0001), respectively. Placebo-corrected mean change in FPG from baseline to week 24 was -21.3 mg/dl (95% CI: -31.0, -11.6; P < 0.0001). The incidence of drug-related adverse events was similar for linagliptin and placebo (10.4% and 8.2%, respectively). Changes in systolic and diastolic blood pressure, cholesterol and triglyceride levels were similar between linagliptin and placebo. CONCLUSION: In T2DM patients with the two common vascular risk factors of hypertension and microalbuminuria, linagliptin achieved significant improvements in glycemic control. In this vulnerable patient population at high risk for micro- and macrovascular complications, linagliptin was well tolerated.