Efficacy and Safety of Azithromycin vs Levofloxacin in the Outpatient Treatment of Acute Bacterial Exacerbations of Chronic Bronchitis

Abstract

To compare the safety and efficacy of oral azithromycin and levofloxacin in the treatment of outpatients with acute bacterial exacerbations of chronic bronchitis (ABECB). Randomized, double-blinded, double-dummy, multicenter trial with 1:1 treatment allocation. Outpatient treatment setting. Two hundred thirty-five male or female outpatients between the ages of 35 and 75 years who had received a clinical diagnosis of ABECB. Blinded treatment with either oral azithromycin, 500 mg on day 1 and 250 mg per day for days 2 to 5, or, oral levofloxacin, 500 mg q24h for 7 days. Both treatments were well-tolerated, with the majority of adverse events being GI in nature. Favorable clinical outcomes in clinically evaluable patients were demonstrated in 89% of patients receiving azithromycin and in 92% of patients receiving levofloxacin by day 4 of therapy. At day 24, the posttherapy visit, favorable responses were approximately 82% and 86%, respectively, for patients in the two treatment groups. The bacterial eradication rates of respiratory pathogens were 96% for azithromycin and 85% for levofloxacin. Despite increasing concerns over macrolide resistance and a higher incidence of Gram-negative pathogens, a standard 5-day course of oral azithromycin was clinically and bacteriologically equivalent to a 7-day course of oral levofloxacin in the treatment of patients with ABECB.