A multicentre study comparing the safety and efficacy of dirithromycin with erythromycin in the treatment of...

This European multicentre (110 centres), double-blind, randomized clinical trial compared the safety and efficacy of dirithromycin (500 mg orally once daily) and erythromycin (250 mg orally qds) in the treatment of either acute bacterial bronchitis or acute bacterial exacerbations of chronic bronchitis. From January 1989 to September 1990, 1222 patients (529 with acute bronchitis and 693 with acute exacerbations of chronic bronchitis) were included in the trial. Clinical and bacteriological evaluations were performed on 135 evaluable patients with acute bronchitis (72 in the dirithromycin group and 63 in the erythromycin group) and in 202 patients with acute exacerbations of chronic bronchitis (89 treated with dirithromycin and 113 treated with erythromycin). Evaluations were performed during treatment (days 3-5), post-therapy (three to five days after therapy completion), and late post-therapy (10-14 days following the end of therapy). In acute bronchitis, both drugs were effective with clinical success rates of 93.0% and 95.2% at post-therapy, and 96.9% and 100% at late post-therapy for dirithromycin and erythromycin, respectively. Pathogen eradication rates at post-therapy were 83.3% for the dirithromycin group and 85.7% for the erythromycin group. In acute exacerbations of chronic bronchitis, the drugs were also effective with 89.9% and 92.1% cure or improvement at post-therapy and 98.7% and 95.0% at late post-therapy for dirithromycin and erythromycin, respectively. Pathogen eradication rates were 75.3% in both treatment groups. There were no statistically significant differences in clinical and bacteriological results between treatments in patients with acute bronchitis or acute exacerbations of chronic bronchitis. Of the 1222 patients included, no significant differences in the number of patients reporting adverse events were observed. There were nine early discontinuations due to adverse events in the dirithromycin group and 14 in the erythromycin group. Dirithromycin (500 mg once daily for seven days) was as effective and as safe as erythromycin (250 mg qid for seven days) in the treatment of acute bacterial bronchitis and acute bacterial exacerbations of chronic bronchitis.