Background: Concurrent use of an inhaled corticosteroid (ICS) and an inhaled long-acting beta2-agonist provides better overall asthma control than the use of higher doses of ICS alone.
Objective: The purpose of this investigation was to determine whether fluticasone propionate (FP) combined with salmeterol in the Diskus device can be used to reduce the dose of ICS in patients currently stable on medium-dose ICS while maintaining asthma control.
Methods: This was a randomized, double-blind, parallel-group, 12- to 24-week trial consisting of a 3-part run-in period. The run-in period was designed to first establish FP 250 microg administered twice a day (bid) via Diskus as the minimum effective dose. During run-in period 1, patients received FP 220 microg bid or the equivalent for 10 to 14 days. Controlled patients moved to run-in period 2 (5-28 days), which assessed asthma stability on FP 100 microg bid administered via Diskus. Only patients who became unstable on FP 100 microg bid were eligible to enter run-in period 3 (26-30 days), during which they were placed on FP 250 microg bid and those regaining asthma control were eligible for randomization. The primary efficacy endpoint was the proportion of patients who remained in the study with no evidence of worsening asthma. Secondary efficacy measures included FEV1, morning peak expiratory flow, percent of symptom-free days, and daily albuterol use.
Results: Only 5% of patients treated with FP100/salmeterol withdrew because of worsening asthma in the first 12 weeks; this compared with 7% in the FP250 group. All patients from a subset of sites continued in the study for an additional 12 weeks; only an additional 1% of patients treated with either FP100/salmeterol or FP250 withdrew because of worsening asthma. Secondary efficacy measures confirmed primary efficacy results.
Conclusion: In patients requiring FP250 bid for asthma stability, FP100/salmeterol bid was steroid-sparing, allowing a 60% reduction in the FP dose while maintaining overall asthma control.