Faster onset of bronchodilation with formoterol than with salmeterol in patients with stable, moderate to severe COPD: results of a randomized, double-blind clinical study

Abstract

Objectives: To compare the onset and magnitude of bronchodilation after dry powder inhalations of formoterol fumarate (Foradil Aerolizer) versus salmeterol xinofoate (Serevent Diskus) with respect to normalized (*) forced expiratory volume in 1 s area under the curve 0 to 1 h after inhalation (FEV1 AUC*0-1 h).

Design: A double-blind, double-dummy, multicentre, randomized, placebo controlled, single-dose, five-period crossover study.

Setting: Five centres in four countries - one centre each in France, Greece and Italy, and two centres in the Netherlands.

Patients: Forty-seven patients aged 42 to 80 years (mean age 63.5 years) with chronic obstructive pulmonary disease (COPD) stage II and III, and mean baseline FEV1 1.17 L (range 0.56 to 1.77 L).

Interventions: Patients inhaled single doses of formoterol dry powder (12 and 24 mg), single doses of salmeterol (50 and 100 mg) and matching placebo on five separate days.

Main results: The estimates of treatment difference in absolute terms (0.086 L) and percentage change from predose baseline (7.8%) for the primary end point, FEV1 AUC*0-1 h, showed that formoterol 12 mg was statistically significantly superior to salmeterol 50 mg (P=0.0044 and P=0.0021, respectively). In addition, both doses of formoterol were statistically superior to placebo for both absolute improvement and percentage change (P=0.0001). The analysis of secondary variables also confirmed the superiority of formoterol over salmeterol.

Conclusions: Formoterol is associated with a faster onset of bronchodilation than salmeterol in patients with COPD.