Tolerability of indacaterol, a novel once-daily β2-agonist, in patients with asthma: a randomized, placebo-controlled, 28-day safety study

Background Indacaterol is a novel, inhaled, once-daily β 2 -agonist. Objective To investigate the safety and tolerability of indacaterol at doses of 400 and 800 μg/d. Methods Randomized, double-blind, placebo-controlled, parallel-group, multicenter, 28-day study. Patients with persistent asthma (forced expiratory volume in 1 second [FEV 1 ] ≥60% predicted, ≤1,600 μg of beclomethasone dipropionate or equivalent daily) received indacaterol, 400 μg (n = 59) or 800 μg (n = 59), or placebo (n = 26) once daily via a single-dose dry powder inhaler. Safety assessments were performed before and after dosing on days 1, 14, and 28, with particular attention to key β 2 -agonist safety variables. Results A total of 144 patients were randomized, with 135 (93.8%) completing the study. Indacaterol was well tolerated: the incidence of adverse events (AEs) was similar between the active and placebo groups, and AEs, when they occurred, were mild or moderate for most (98.2%). There was no dose-response relationship between indacaterol and the incidence of AEs (400 μg, 40.7%; 800 μg, 37.3%; and placebo, 38.5%). Few AEs considered as β 2 -agonist class effects occurred (none leading to withdrawal). Small differences between indacaterol and placebo in mean serum potassium (≤−0.29 mmol/L) and glucose (≤0.93 mmol/L) levels were occasionally statistically significant ( P 2 -agonist, there was some indication of a trend in QTc prolongation with increasing exposure (maximum mean change, 8.9 milliseconds; P 1 ( P Conclusion Indacaterol had a good overall safety profile and was well tolerated at both doses, with predose FEV 1 results on days 14 and 28 indicating 24-hour bronchodilator efficacy.