INSTEAD: a randomised switch trial of indacaterol versus salmeterol/fluticasone in moderate COPD.

The Indacaterol: Switching Non-exacerbating Patients with Moderate COPD From Salmeterol/Fluticasone to Indacaterol (INSTEAD) study investigated the effect of switching patients at low risk of chronic obstructive pulmonary disease (COPD) exacerbations from salmeterol/fluticasone (SFC; inhaled corticosteroid (ICS) regimen) to indacaterol monotherapy (non-ICS regimen). This 26-week, double-blind, double-dummy, parallel-group, phase IV study, randomised 581 patients with moderate COPD to indacaterol 150 μg once daily or SFC 50/500 μg twice daily. Patients had been receiving SFC 50/500 μg for ≥3 months, with no COPD exacerbations for more than a year before the study (patients for whom ICS is not recommended). The primary objective was to demonstrate non-inferiority of indacaterol to SFC, measured by trough forced expiratory volume in 1 second (FEV₁) after 12 weeks (non-inferiority margin of 0.06 L). The primary objective was met, with a mean treatment difference of 9 mL (95% CI -45-26 mL). There were no significant differences between treatments in terms of breathlessness (transition dyspnoea index) or health status (Saint George's Respiratory Questionnaire) at weeks 12 or 26, or rescue medication use or COPD exacerbation rates over 26 weeks. Safety profiles of both treatments were as expected. This study demonstrated that patients with moderate COPD and no exacerbations in the previous year can be switched from SFC to indacaterol 150 μg with no efficacy loss.