Inhaled formoterol dry powder in the treatment of patients with reversible obstructive airway disease. A 3-month, placebo-controlled comparison of the efficacy and safety of formoterol and salbutamol, followed by a 12-month trial with formoterol.

Abstract

Inhaled formoterol is a potent selective beta 2-agonist with rapid onset and at least 12-h duration of bronchodilation. The aim of the study was to compare the bronchodilating effect of inhaled formoterol dry powder (dp) 12 micrograms b.i.d. with salbutamol dp 400 micrograms q.i.d. and placebo in patients with reversible obstructive airway disease (ROAD). The study design consisted of a closed 12-week double-blind, placebo-controlled, multicenter trial followed by an open noncomparative, multicenter, 12-month follow-up trial, in which the tolerability of formoterol dp was assessed. A total of 304 patients (146 men, 158 women) aged 18-79 years, ill during 0.1-64 years, were randomized. No demographic or baseline differences were found among the different treatment groups. The bronchodilating effect of formoterol, assessed by morning premedication PEFR, was significantly superior to placebo (P < 0.0001) and salbutamol (P < 0.0001). Efficacy was maintained during the open follow-up study with 12 micrograms b.i.d. in most of the patients. A few patients, however, needed 24 micrograms b.i.d. to control their ROAD. Formoterol 12 micrograms b.i.d. significantly reduced morning and evening asthma symptoms and sleep disturbances, and reduced significantly the need for rescue medication. The tolerability of the three treatment groups was comparable. In conclusion, formoterol 12 micrograms dp b.i.d. was significantly superior to both salbutamol 400 micrograms dp q.i.d. and placebo, and reduced asthma symptoms significantly. Overall, formoterol showed a tolerability profile comparable to that of salbutamol, and no tachyphylaxis was observed during 1 year of treatment.