Objectives: This multicentre, parallel group, double-blind, double-dummy, randomised 24-week study was designed to compare the efficacy of salmeterol/fluticasone propionate combination (SFC) 50/250 microg one inhalation twice daily (bid) with formoterol/budesonide combination (FBC) 6/200 microg two inhalations bid in patients with persistent asthma, currently receiving 1000-2000 microg/day of inhaled corticosteroids.
Methods: The intent-to-treat population comprised 694 patients in the SFC group and 697 patients in the FBC group.
Results: The primary endpoint, mean rate of all exacerbations over 24 weeks, was similar in both treatment groups (SFC: 2.69; FBC: 2.79; SFC/FBC ratio 0.96; 95% CL 0.84, 1.10; P=0.571). A reduction in the rate of exacerbations over time was observed in both treatment groups. Overall, there was a 30% lower annual rate of moderate/severe exacerbations in the SFC group compared with the FBC group (95% CI 0-49%, 52% reduction vs. 1% increase; P=0.059). This effect increased with time: in weeks 17-24 the moderate/severe exacerbation rate was 57% lower in the SFC group compared with the FBC group (95% CI 21-77% reduction; P=0.006). Similar improvements in lung function, asthma symptoms and rescue medication usage were seen with both treatments and both were well tolerated.
Conclusions: Twice-daily treatment with SFC and FBC over 6 months significantly improved asthma symptoms and lung function in patients with persistent asthma. The rate of exacerbations was significantly reduced over time on both treatments but SFC was found to be significantly superior to FBC in reducing the rate of moderate/severe exacerbations with sustained treatment.