Efficacy of indacaterol/glycopyrronium versus salmeterol/fluticasone in current and ex-smokers: a pooled analysis of IGNITE trials

Abstract

Inhaled corticosteroids have proven to be less effective in asthmatic patients who smoke; however, there is limited information on the efficacy of inhaled corticosteroid-containing regimens in COPD patients who continue smoking. We evaluate the differential efficacy of once-daily indacaterol/glycopyrronium 110/50 µg compared with twice-daily salmeterol/fluticasone 50/500 µg in current smokers and ex-smokers with COPD. A pooled analysis of data from ILLUMINATE, LANTERN and FLAME studies was conducted to assess the efficacy of indacaterol/glycopyrronium compared with salmeterol/fluticasone in current smokers and ex-smokers with COPD. Efficacy was assessed in terms of improvements in trough forced expiratory volume in 1 s (FEV1), transition dyspnoea index (TDI) focal score, St George's Respiratory Questionnaire (SGRQ) total score, reduced rescue medication use and exacerbation prevention at 26 weeks after the start of the therapy. In total, 1769 (38%) current smokers and 2848 (62%) ex-smokers were included. Patients treated with indacaterol/glycopyrronium experienced greater improvements in trough FEV1 versus salmeterol/fluticasone in both current and ex-smokers (least squares mean treatment difference, 105 mL and 78 mL, respectively). Improvements in TDI focal score, SGRQ total score and reduction in rescue medication use were also greater with indacaterol/glycopyrronium versus salmeterol/fluticasone in current and ex-smokers. Furthermore, indacaterol/glycopyrronium reduced all exacerbations (moderate/severe) compared with salmeterol/fluticasone, irrespective of smoking status. The difference in efficacy in favour of indacaterol/glycopyrronium was more prominent in current smokers in most cases. Indacaterol/glycopyrronium demonstrated greater efficacy versus salmeterol/fluticasone, and the differences were generally more prominent in current smokers suggesting smoking may reduce the effects of salmeterol/fluticasone.