A comparison of clarithromycin with ampicillin in the treatment of outpatients with acute bacterial exacerbation of chronic bronchitis.

One hundred and twenty-five outpatients with clinical symptoms of an acute bacterial exacerbation of chronic bronchitis were enrolled in a multicentre, double-blind, randomized clinical trial to compare the efficacy and safety of oral clarithromycin and ampicillin. Only those patients presenting with pathogens cultured from pre-treatment specimens susceptible to both study drugs were included in the study; beta-lactamase producing strains were excluded. Sixty patients received clarithromycin 250 mg 12-hourly and 65 had ampicillin 250 mg 6-hourly for 7-14 days. Clinical and bacteriological evaluations were performed pre-treatment, during treatment, and post-treatment within 48 h of cessation of therapy. All adverse events reported were evaluated. Twenty patients from the clarithromycin group and 24 from the ampicillin group were withdrawn from the study when no pathogen was isolated from the pre-treatment specimens. Twenty-eight patients who received clarithromycin and 23 who received ampicillin were evaluable for clinical and bacteriological efficacy. Both treatment groups were similar with respect to clinical and bacteriological response rates. The clinical cure rate for clarithromycin was 96% (27/28) compared with 91% (21/23) for the ampicillin group. Clarithromycin achieved a bacteriological cure rate of 96% (27/28) compared with 100% (23/23) for the ampicillin group. Adverse events, which were generally mild and associated with the digestive system, were reported by 11.7% of patients receiving clarithromycin and 1.5% of patients receiving ampicillin. Adverse events caused two patients in each group to discontinue treatment. Laboratory profiles for both groups were unremarkable throughout treatment.(ABSTRACT TRUNCATED AT 250 WORDS)