Clinical Question: Is moxifloxacin more effective than alternatives for acute exacerbation of chronic bronchitis?

Setting: Outpatient (specialty)

Study Design: Randomized controlled trial (double-blinded)

Synopsis: Adults older than 45 years who had chronic bronchitis, at least 20 pack-years of smoking, at least two previous acute exacerbations of chronic bronchitis, and a forced expiratory volume in one second of less than 85 percent of predicted were studied. They were randomized (allocation concealed) at the time of a new acute exacerbation, defined as increased dyspnea, increased sputum volume, and purulent sputum.

If randomized to the treatment group, the patients received moxifloxacin in a dosage of 400 mg orally once a day for five days. Patients in the control group received amoxicillin in a dosage of 500 mg orally three times a day for seven days (n = 88), clarithromycin in a dosage of 500 mg orally twice a day for seven days (n = 114), or cefuroxime axetil in a dosage of 250 mg orally twice a day for seven days (n = 174) at their physician’s discretion. Patients were contacted by telephone approximately one week after randomization and examined seven to 10 days after the end of treatment. Analysis was by intention to treat, and groups were similar at baseline.

The primary patient-oriented outcome was clinical success, defined as the percentage of patients who were cured or improved to the point that no additional antimicrobial therapy was necessary, seven to 10 days after treatment ended. This outcome was achieved in 87.6 percent of the moxifloxacin group, 83.0 percent of the amoxicillin group, 84.2 percent of the clarithromycin group, and 82.2 percent of the cefuroxime axetil group (P = not significant). The rate of complete clinical cure was slightly higher in the moxifloxacin group than in the combined comparison groups (70.9 percent versus 62.8 percent; number needed to treat = 12.5). Adverse events were more common in the moxifloxacin group (7.1 percent versus 4.8 percent; statistical significance not reported).

Bottom Line: In terms of complete clinical cure one week after the end of treatment, moxifloxacin offers a small advantage over the alternatives (i.e., amoxicillin, clarithromycin, or cefuroxime axetil) for the treatment of acute exacerbation of chronic bronchitis, but no advantage in terms of overall clinical success. Because the much less expensive and better tolerated amoxicillin offered a very similar overall clinical success rate (83.0 percent versus 87.6 percent for moxifloxacin), it should remain the treatment of choice for most patients. (Level of Evidence: 1b)