Comparable pharmacodynamics, efficacy, and safety of linagliptin 5 mg among Japanese, Asian and white patients with type 2 diabetes

AIMS/INTRODUCTION The efficacy and safety of drugs can vary between different races or ethnic populations because of differences in the relationship of dose to exposure, pharmacodynamic response or clinical efficacy and safety. In the present post-hoc analysis, we assessed the influence of race on the pharmacokinetics, pharmacodynamics, efficacy and safety of monotherapy with the dipeptidyl peptidase-4 inhibitor, linagliptin, in patients with type 2 diabetes enrolled in two comparable, previously reported randomized phase III trials. MATERIALS AND METHODS Study 1 (with a 12-week placebo-controlled phase) recruited Japanese patients only (linagliptin, n = 159; placebo, n = 80); study 2 (24-week trial) enrolled Asian (non-Japanese; linagliptin, n = 156; placebo, n = 76) and white patients (linagliptin, n = 180; placebo, n = 90). RESULTS Linagliptin trough concentrations were equivalent across study and race groups, and were higher than half-maximal inhibitory concentration, resulting in dipeptidyl peptidase-4 inhibition >80% at trough. Linagliptin inhibited plasma dipeptidyl peptidase-4 activity to a similar degree in study 1 and study 2. Linagliptin reduced fasting plasma glucose concentrations by a similar magnitude across groups, leading to clinically relevant reductions in glycated hemoglobin in all groups. Glycated hemoglobin levels decreased to a slightly greater extent in study 1 (Japanese) and in Asian (non-Japanese) patients from study 2. Linagliptin had a favorable safety profile in each race group. CONCLUSIONS Trough exposure, pharmacodynamic response, and efficacy and safety of linagliptin monotherapy were comparable among Japanese, Asian (non-Japanese) and white patients, confirming that the recommended 5-mg once-daily dose of linagliptin is appropriate for use among different race groups.