A comparison of gemifloxacin and clarithromycin in acute exacerbations of chronic bronchitis and long-term clinical outcomes.

BACKGROUND

Gemifloxacin is an enhanced-affinity quinolone with potent activity against lower respiratory tract pathogens.

OBJECTIVE

The efficacy and safety of a 5-day course of gemifloxacin were compared with those of a standard 7-day regimen of clarithromycin in patients with an acute exacerbation of chronic bronchitis (AECB). The impact of treatment on the long-term (26 weeks) clinical outcome was also assessed.

METHODS

The acute phase of this randomized, double-blind study was performed in 93 centers in 7 countries. Adult patients (age >40 years) with a history of chronic bronchitis and an Anthonisen type 1 acute exacerbation (increased dyspnea, cough, and sputum purulence) were eligible. Patients receiving systemic steroids at a dose of >10 mg prednisone or the equivalent were excluded. Patients were randomized to receive gemifloxacin 320 mg once daily for 5 days or clarithromycin 500 mg twice daily for 7 days. Clinical and bacteriologic response rates were assessed at the end-of-therapy visit (days 8-12), the week 2-3 follow-up visit (days 13-24), and the week 4-5 follow-up visit (days 25-38). The long-term phase (26 weeks), which included US and Canadian participants only, evaluated the proportion of patients who remained free of a recurrence of AECB requiring additional antimicrobial therapy after resolution of the initial episode.

RESULTS

Seven hundred twelve patients were randomized to treatment, 351 to gemifloxacin and 361 to clarithromycin. The long-term study included 438 patients, 214 receiving gemifloxacin and 224 receiving clarithromycin. Clinical success rates at the 2-3 week follow-up visit were 85.4% for gemifloxacin and 84.6% for clarithromycin. Bacteriologic success rates were 86.7% for gemifloxacin and 73.1% for clarithromycin. Significantly more patients receiving gemifloxacin than clarithromycin remained free of AECB recurrences (71.0% vs 58.5%, respectively; P = 0.016). Both treatments were well tolerated.

CONCLUSIONS

In the acute treatment of Anthonisen type 1 AECB, a 5-day course of gemifloxacin was at least as effective as a 7-day regimen of clarithromycin. In this population, significantly more patients receiving gemifloxacin remained free of AECB recurrence after 26 weeks compared with those receiving clarithromycin.