Once-daily mometasone plus indacaterol versus mometasone or twice-daily fluticasone plus salmeterol in patients with inadequately controlled asthma (PALLADIUM): a randomised, double-blind, triple-dummy, controlled phase 3 study

Fixed-dose combinations (FDCs) of inhaled corticosteroids (ICS) and long-acting β2-adrenoceptor agonists (LABA) are considered safe and efficacious in asthma management. Most available FDCs require twice-daily dosing to achieve optimum therapeutic effect. The objective of the PALLADIUM study was to assess the efficacy and safety of once-daily FDC of mometasone furoate plus indacaterol acetate (MF–IND) versus mometasone furoate (MF) monotherapy in patients with inadequately controlled asthma. This 52-week, double-blind, triple-dummy, parallel-group, phase 3 study recruited patients from 316 centres across 24 countries. Patients aged 12 to 75 years with a documented diagnosis of asthma for at least 1 year, percentage of predicted FEV1 of 50–85%, and an Asthma Control Questionnaire 7 score of at least 1·5 despite treatment with medium-dose or high-dose ICS or low-dose ICS plus LABA were included. A history of asthma exacerbations was not a study requirement. Participants were randomily assigned (1:1:1:1:1) via interactive response technology to receive one of the following treatments for 52 weeks: high-dose MF–IND (320 μg, 150 μg) or medium-dose MF–IND (160 μg, 150 μg) once daily via Breezhaler; high-dose MF (800 μg [400 μg twice daily]) or medium-dose MF (400 μg once daily) via Twisthaler; or high-dose fluticasone propionate–salmeterol xinafoate (FLU–SAL; 500 μg, 50 μg) twice daily via Diskus. Participants received placebo via inhalation through the Breezhaler, Twisthaler, or Diskus devices in the mornings and evenings, as appropriate. The primary endpoint was improvement in trough FEV1 with high-dose and medium-dose MF–IND versus respective MF doses from baseline at 26 weeks, analysed in the full analysis set by means of a mixed model for repeated measures. High-dose MF–IND once daily was compared with high-dose FLU–SAL twice daily for non-inferiority on improving trough FEV1 at week 26 with a margin of −90 mL using mixed model for repeated measures as one of the secondary endpoints. Safety was assessed in all patients who had received at least one dose of study drug. This study is registered with ClinicalTrials.gov, NCT02554786, and is completed. Between Dec 29, 2015, and May 4, 2018, 2216 patients were randomly assigned (high-dose MF–IND, n=445; medium-dose MF–IND, n=439; high-dose MF, n=442; medium-dose MF, n=444; high-dose FLU–SAL, n=446), of which 1973 (89·0%) completed the study treatment and 234 (10·6%) prematurely discontinued study treatment. High-