Loracarbef (LY163892) versus amoxicillin/clavulanate in the treatment of acute bacterial exacerbations of chronic bronchitis.

In this single-blind study, 579 patients with chronic bronchitis were randomly assigned to receive 400 mg of loracarbef twice daily or 500/125 mg of amoxicillin/clavulanate thrice daily for seven days. Treatment efficacy was evaluated in 129 of the loracarbef-treated patients and 120 amoxicillin/clavulanate-treated patients in whom pretreatment positive cultures of pathogens susceptible to both antibiotics were isolated. Three organisms predominated in either pure or mixed cultures in 57.0% of the evaluable patients: Haemophilus influenzae, Streptococcus pneumoniae, or Moraxella (Branhamella) catarrhalis; H influenzae was isolated in 25.0% of the patients with single pathogens. Among the evaluable patients, favorable clinical responses (cure or improvement) were noted in 93.8% of the loracarbef-treated patients and in 95.0% of the amoxicillin/clavulanate-treated patients. A favorable bacteriologic response (pathogen eliminated or presumed eliminated) was found in 82.2% of loracarbef-treated patients and 90.0% of amoxicillin/clavulanate-treated patients. Six patients in the loracarbef group and 14 in the amoxicillin/clavulanate group discontinued treatment because of adverse events. The events were judged to be drug related in four loracarbef-treated patients and in 11 amoxicillin/clavulanate-treated patients. The incidence of diarrhea and other gastrointestinal symptoms was significantly more frequent in the amoxicillin/clavulanate group (13.5% and 5.6%) than in the loracarbef group (4.5% and 1.7%), while the incidence of severe headaches was significantly more frequent in the loracarbef than the amoxicillin/clavulanate group (7.2% vs 3.1%). It is concluded that loracarbef and amoxicillin/clavulanate are safe and effective in the treatment of acute bacterial exacerbations of chronic bronchitis.