Efficacy and Safety of Indacaterol, a New 24-hour β₂-Agonist, in Patients with Asthma: A Dose-Ranging Study

Abstract

Background. Indacaterol is a new once-daily inhaled β₂-agonist in clinical development for asthma as a component of a fixed-dose combination with an inhaled corticosteroid. Objectives. To investigate the efficacy and safety of indacaterol in patients with chronic persistent asthma. Methods. A total of 115 patients were randomized in a double-blind, incomplete-block cross-over design to sequences of four 7-day treatment periods (separated by 7-day washouts) with indacaterol 100, 200, 300, 400, or 600 μ g or placebo, once daily, via single-dose dry-powder inhaler. After the fourth washout, patients received 1 day of open-label formoterol 12 μ g twice daily. Forced expiratory volume in 1 second (FEV₁) was measured for 24 hours post-dose on days 1 and 7. Results. For standardized (with respect to time) FEV₁ area under the curve at 22 to 24 hours (AUC_22–24h) on day 1, indacaterol doses ≥200 μ g were superior to placebo (p < 0.05) and similar or greater than formoterol 12 μg twice daily. By day 7, mean differences from placebo in FEV₁ standardized AUC_22–24h were 0.08, 0.16, 0.15, 0.11, and 0.16 L for indacaterol 100, 200, 300, 400, and 600 μg, respectively (all p < 0.05 vs. placebo). Mean FEV₁ for indacaterol doses ≥ 200 μg on day 7 was higher than placebo (p < 0.05) pre-dose and at all post-dose time points. AEs were generally mild in severity; no serious AEs occurred. No clinically meaningful differences were observed between treatments in any safety assessments. Conclusions. Once-daily indacaterol demonstrated sustained 24-hour bronchodilator efficacy, with similar efficacy on days 1 and 7, and was generally well tolerated.

Keywords:

• asthma
• long-acting β₂-agonist
• indacaterol
• bronchodilator
• efficacy