A twelve-week comparison of salmeterol and salbutamol in the treatment of mild-to-moderate asthma: a Canadian multicenter study.

Abstract

A long-acting inhaled bronchodilator that is both well tolerated and effective could allow for improved control of both daytime and nighttime symptoms in patients with asthma who use frequent as-needed short-acting bronchodilators despite antiinflammatory treatment. We compared the efficacy and safety of inhaled salmeterol, 50 micrograms twice daily, with inhaled salbutamol, 200 micrograms four times daily, delivered through a metered-dose inhaler for 3 months in a multicenter, randomized, double-blind, parallel-group study of 228 patients (aged 12 to 76 years) with mild-to-moderate asthma. A single morning dose of salmeterol produced improvement in FEV1 that was significantly greater (p < or = 0.012) than that produced by two doses of salbutamol (taken 6 hours apart) when patients were assessed 3 to 6 hours and 10 to 12 hours after the dose. This greater bronchodilation was present on day 1 of the study and after 4, 8, and 12 weeks of regular treatment. Over the 12 weeks, compared with salbutamol, salmeterol treatment was associated with a greater mean improvement in morning peak expiratory flow (35 L/min vs -3 L/min, p < 0.001), a higher percentage of days with no symptoms (29% vs 15%; p = 0.012), and a higher percentage of nights with no awakenings (14% vs -1%; p < 0.001). Adverse events were similar for both treatments. In this study salmeterol, 50 micrograms twice daily, was well tolerated and more effective than salbutamol, 200 micrograms four times daily, in improving symptoms and lung function in patients with mild-to-moderate asthma.