A 6-MONTH COMPARISON BETWEEN FORMOTEROL AND SALMETEROL IN PATIENTS WITH REVERSIBLE OBSTRUCTIVE AIRWAYS DISEASE

The aim of this randomized, open, parallel group study was to compare the clinical efficacy of formoterol dry powder capsule 12 mu g b.i.d. and salmeterol dry pow der 50 mu g b.i.d. in the treatment of patients with reversible obstructive airways disease. The 6-month treatment wa s preceded by a 2 week run-in period. Morning pre-dose peak expiratory flow (PEF) during the last 7 days of treatment was the primary variab le. Throughout the study, patients recorded morning and evening pre-do se PEF, use of rescue medication, respiratory symptoms and adverse eve nts. Clinic visits were scheduled at monthly intervals. Of the 482 pat ients randomized (equal numbers in the two treatment groups), 428 comp leted the study. Four hundred and twenty-five patients were included i n the efficacy analysis for the primary variable. For mean morning pre -dose PEF during the last 7 days of treatment, the 95% confidence inte rval (CI) for the treatment contrast formoterol minus salmeterol was i ncluded entirely in the pre-defined range of equivalence (CI limits = - 8.69, + 9.841 min(-1)). This was also the case for the morning PEF d uring the last week before each clinic visit. For mean evening pre-dos e PEF, the estimated treatment contrasts showed a trend towards superi ority of formoterol over salmeterol. which became statistically signif icant at 2, 3 and 4 months (P < 0.05; estimated contrasts 7.27, 10.45 and 10.51 l min(-1), respectively). No treatment group differences wer e found in use of rescue medication and respiratory symptom scores. Th e incidence of adverse events was similar in the two groups.These find ings demonstrate that formoterol 12 mu g b.i.d. and salmeterol 50 mu g b.i.d., both formulated as dry powders, have similar long-term effica cy and safety profiles in patients with reversible obstructive airways disease.