Formoterol, a new long-acting beta 2 agonist, inhaled twice daily, in stable asthmatic subjects

To determine whether formoterol, a new beta 2 agonist with experimentally documented long duration, is clinically more effective than salbutamol in the maintenance treatment of chronic asthma.

Randomized double-blind between-patient comparison between treatment with formoterol and with salbutamol during four weeks.

Asthma/allergy department in a university hospital.

Thirty-seven patients with chronic stable asthma, who during a two-week run-in period with inhaled salbutamol, 4 x 100 micrograms twice a day, used at least four additional doses (100 micrograms each) daily, were randomly assigned to use either formoterol or salbutamol. Thirty-five patients were evaluated for efficacy. One early withdrawal and one dropout were found in the salbutamol group. The groups were similar with respect to demographic data and baseline lung function.

During the four-week study period, the patients used either formoterol (4 x 6 micrograms twice a day and as necessary, n = 19) or salbutamol (4 x 100 micrograms twice a day and as necessary, n = 16). Inhaled steroids and orally administered theophylline were allowed if doses were kept constant.

The median number of additional doses per 24 h (median of two weeks) of the test aerosols was 0 (range, 0 to 6) for formoterol and 4 (range, 0 to 14) for salbutamol (p less than 0.01). Morning and evening PEFRs were 422 (SEM = 31) and 443 (SEM = 30), respectively, for formoterol, and 335 (SEM = 30) and 360 (SEM = 26), respectively, for salbutamol (p = 0.05 for both). Formoterol was superior (p less than 0.05) to salbutamol with respect to control of asthma symptoms, estimated duration of action and patient preference. Side effects did not differ.

Inhaled formoterol administered twice a day and as necessary was clinically more effective than the same regimen of salbutamol.