Safety and efficacy of lomefloxacin versus cefaclor in the treatment of acute exacerbations of chronic bronchitis.

In two multicenter trials, lomefloxacin and cefaclor were compared as treatments for acute bacterial exacerbations of chronic bronchitis. In total, 522 adult outpatients were enrolled at 50 centers in the United States. Patients were randomized to treatment groups receiving either 400 mg lomefloxacin orally once daily (n = 259) or 250 mg cefaclor every 8 hours (n = 263) for 7-10 days. Both groups were comparable in terms of age, severity of exacerbation, smoking history, theophylline use, and baseline pathogens. The most common baseline pathogens were Haemophilus influenzae, found in 32% of patients in the lomefloxacin group and in 29% in the cefaclor group, Pseudomonas aeruginosa (13% and 16%, respectively), Moraxella (Branhamella) catarrhalis (12% and 13%), and Streptococcus pneumoniae (10% in both groups). Bacterial eradication rates 1-4 days after the completion of treatment for all patients with baseline pathogens were 81.8% in the lomefloxacin group and 62.7% in the cefaclor group (p less than 0.001). Clinical success (disappearance or improvement of presenting signs and symptoms) was noted in 80.0% of patients in the lomefloxacin group and 64.7% in the cefaclor group (p = 0.002). Eradication rates for the subgroup of patients who had pathogens susceptible in vitro to both study drugs and who completed treatment were 97.1% for lomefloxacin and 84.6% for cefaclor (p = 0.002). Clinical success rates in this subgroup were 92.4% for lomefloxacin and 90.1 for cefaclor (p = 0.585). Treatment-related adverse events were reported for 7% of patients in the lomefloxacin group and 5% in the cefaclor group. The most common adverse events in both groups were nausea and diarrhea. Six patients were withdrawn from treatment with lomefloxacin and four from the cefaclor group because of adverse events. There was no clinical or laboratory evidence of theophylline interaction with either treatment. Once-daily oral administration of 400 mg lomefloxacin was an effective, well-tolerated alternative to 250 mg of cefaclor three times daily in the treatment of acute exacerbations of chronic bronchitis.