Assessing efficacy of indacaterol in moderate and severe COPD patients: A 12-week study in an Asian population

Introduction: This post hoc analysis evaluated the efficacy of indacaterol, a novel inhaled once-daily long-acting β₂-agonist, by disease severity (GOLD 2005) in patients with moderate-to-severe COPD from six Asian countries/areas (Hong Kong, India, Japan, Korea, Singapore, Taiwan). Methods: Data from a 12-week, double-blind, placebo-controlled, parallel-group study in patients randomized to indacaterol 150 μg, indacaterol 300 μg or placebo once daily were analyzed based on baseline disease severity (moderate or severe). Endpoints were: trough FEV₁ (average of 23 h 10 min and 23 h 45 min post-dose values), transition dyspnoea index (TDI) and St George's Respiratory Questionnaire (SGRQ) at Week 12. Safety data were collected. Results: Of 347 patients randomized, 59.7% had moderate, and 40.3% had severe COPD. Least squares means (LSMs) indacaterol-placebo differences in trough FEV₁ at Week 12 exceeded the pre-specified minimal clinically important difference (MCID) of 0.12L and were statistically superior (p < 0.001) for indacaterol (150 μg, 300 μg) versus placebo in the two subgroups [0.19L, 0.20L (moderate); 0.15L, 0.19L (severe) respectively]. LSM TDI scores for both indacaterol doses versus placebo in both subgroups were statistically superior (p < 0.05) and clinically meaningful (≥1 unit). Both indacaterol doses showed improvements in LSM SGRQ total scores at Week 12 which exceeded the MCID (4 units) versus placebo in both subgroups, with indacaterol 300 μg-placebo difference in the severe subgroup being statistically significant (p < 0.01). Overall incidence of adverse events was lower with indacaterol than with placebo across both subgroups. Conclusions: Indacaterol demonstrated clinically relevant improvements versus placebo in lung function, dyspnea and health status in Asian COPD patients irrespective of disease severity. Clinical Trials Identifier: NCT00794157.