Effect of an additional dose of indacaterol in COPD patients under regular treatment with indacaterol.

Abstract: Aim: In this randomized, double-blind, crossover study, we explored the acute effects on respiratory function and safety of an additional dose of indacaterol 150 mu g in stable COPD patients regularly treated with a conventional dose of indacaterol 150 mu g. Methods: On two non-consecutive days, patients inhaled indacaterol 150 mu g. After 180 min, they inhaled an additional dose of indacaterol 150 mu g or placebo. Lung function, oxygen saturation by pulse oxinnetry (SpO(2)) and heart rate were measured before the first drug administration and up to 360 min thereafter. Results: In both treatment groups, indacaterol induced a significant (P < 0.05) bronchodilation during all the study time. The difference between the FEV1 AUCS(0-180) min was not statistically significant (P = 0.971). On the contrary, the difference between the FEV1 AUCs(180-360) min was significant (P < 0.0001). However, only 8 out of 20 patients showed a further increase of at least 100 ml from the peak obtained after the first administration of indacaterol 150 mu g with the second dose of 150 mu g. I ndacaterol 150 mu g induced a modest but significant decrease in SpO(2) up to 60 min and a second dose of indacaterol 150 mu g significantly decreased the SpO(2) mean value up to 360 min. Conclusion: This study suggests that it is reasonable and safe to increase the dose of indacaterol in those stable COPD patients who are under regular therapy with indacaterol 150 mu g from which they do not draw the maximum benefit because they are unable to perceive bronchodilation. However, only a minority of patients seem to benefit from this dose escalation, at least in terms of spirometric improvement. (C) 2012 Elsevier Ltd. All rights reserved.