Background: Salmeterol, a long-acting beta2 -agonist, and zafirlukast, a leukotriene receptor antagonist, are both indicated for the treatment of asthma in adolescent and adult patients.
Objective: We sought to compare the effect of 4 weeks of treatment with inhaled salmeterol xinafoate versus oral zafirlukast in the treatment of persistent asthma.
Methods: This was a randomized, double-blind, double-dummy, parallel-group, multicenter clinical trial. Patients, over 80% of whom were on a concurrent inhaled corticosteroid regimen, were treated for 4 weeks with either inhaled salmeterol xinafoate 42 microgram twice daily administered by means of a metered-dose inhaler or oral zafirlukast 20 mg twice daily. The primary efficacy measure was morning peak expiratory flow (PEF); secondary efficacy measures included evening PEF, asthma symptom scores, supplemental albuterol use, nighttime awakenings, sleep symptoms, asthma exacerbations, and FEV1.
Results: Both inhaled salmeterol and oral zafirlukast resulted in within-group improvements from baseline in measures of pulmonary function, asthma symptoms, and supplemental albuterol use. Salmeterol treatment resulted in significantly greater improvements from baseline compared with zafirlukast for most efficacy measurements, including morning PEF (29.6 vs 13.0 L/min; P </= .001), percentage of symptom-free days (22.4% vs 8.8%; P </= .001), and percentage of days and nights with no supplemental albuterol use (30.5% vs 11.3%; P </= .001). There were no differences in safety profiles as assessed by adverse event monitoring.
Conclusion: In patients with persistent asthma, most of whom were concurrently using inhaled corticosteroids, treatment with inhaled salmeterol provided significantly greater improvement than oral zafirlukast in overall asthma control over the 4-week treatment period.