A multicenter study of nebulized bronchodilator solutions in chronic obstructive pulmonary disease

A multicenter, 85-day, double-blind, randomized study was conducted to compare the effects of a single-dose and chronic inhalation of ipratropium bromide solution (500 micrograms) to the beta-adrenergic agonist metaproterenol (5% solution, 15 mg) in patients with chronic obstructive pulmonary disease (COPD). Patients were required to have a relatively stable, moderately severe COPD, forced expiratory volume in 1 second (FEV1) < 65% of predicted normal, FEV1 <70% of forced vital capacity (FVC), and a smoking history of > 10 pack-years. Following a 2-week baseline period, patients were randomized into either the ipratropium bromide (106 patients) or metaproterenol (107 patients) study groups. Pulmonary function testing was performed on days 1, 43, and 85. Secondary efficacy variables examined included peak expiratory flow rates, physician's global evaluation, quality of life, COPD symptom score, and use of concomitant medications. FEV1 was comparable between the two groups on day 1 (1.00 and 1.02 liters, ipratropium bromide vs metaproterenol, respectively; p = nonsignificant). The baseline FEV1 increased significantly in the ipratropium bromide group between day 1 and 43 by 10% (from 1.00 to 1.10 liters, p < 0.002) and remained 7% elevated on day 85 (1.07 liters) compared to day 1 (p < 0.02); it did not change in the metaproterenol group across all three test days. A clinically significant (> 15%) mean FEV1 response was observed on each of the 3 test days following drug inhalation in both treatment groups. The median duration of action was similar between groups (5 hours) on test day 1, but on day 85 the median duration for ipratropium bromide was r.5 hours compared to 3.0 hours for metaproterenol (p < 0.04). The secondary efficacy variables were uniformly better in the ipratropium bromide than the metaproterenol group. Side effects were infrequent and generally mild in both groups. These data suggest that the availability of a high-dose ipratropium bromide solution offers a safe and effective means of producing prolonged bronchodilation in patients with COPD.