Efficacy of Salmeterol Xinafoate in the Treatment of COPD*

Study objectives: To examine and compare the efficacy and safety of salmeterol xinafoate, a long-acting inhaled b2-adrenergic agonist, with inhaled ipratropium bromide and inhaled placebo in patients with COPD. Design: A stratified, randomized, double-blind, double-dummy, placebo-controlled, parallel group clinical trial. Setting: Multiple sites at clinics and university medical centers throughout the United States. Patients: Four hundred eleven symptomatic patients with COPD with FEV1 < 65 % predicted and no clinically significant concurrent disease. Interventions: Comparison of inhaled salmeterol (42 mg twice daily), inhaled ipratropium bromide (36 mg four times a day), and inhaled placebo (2 puffs four times a day) over 12 weeks. Results: Salmeterol xinafoate was significantly (p < 0.0001) better than placebo and ipratropium in improving lung function at the recommended doses over the 12-week trial. Both salmeterol and ipratropium reduced dyspnea related to activities of daily living compared with placebo; this improvement was associated with reduced use of supplemental albuterol. Analyses of time to first COPD exacerbation revealed salmeterol to be superior to placebo and ipratropium (p < 0.05)