A randomized, double-blind, multicenter comparison of gatifloxacin versus ciprofloxacin in the treatment of complicated urinary tract infection and pyelonephritis

BACKGROUND: Gatifloxacin is a fluoroquinolone antibiotic with a broad spectrum of in vitro and in vivo activity against the gram-negative and gram-positive pathogens frequently implicated in urinary tract infections (UTIs). OBJECTIVE: This study compared the clinical and bacteriologic efficacy and tolerability of gatifloxacin versus ciprofloxacin in adult patients with complicated UTIs or pyelonephritis. METHODS: In this double-blind, multicenter, randomized, comparative study, patients were treated with either gatifloxacin 400 mg once daily or ciprofloxacin 500 mg twice daily for 7 to 10 days. Bacteriologic eradication (by quantitative urine culture) and clinical efficacy rates were assessed at a test-of-cure visit (5 to 9 days and 4 to 11 days posttreatment, respectively) and at an extended follow-up visit (29-42 days and 25-50 days posttreatment, respectively). RESULTS: A total of 372 adults were randomized to treatment, 189 to gatifloxacin and 183 to ciprofloxacin. The most commonly isolated pretreatment pathogens (n = 292) were Escherichia coli (53%) and Klebsiella pneumoniae (13%). Pathogen eradication rates for complicated UTIs were 92% and 83% with gatifloxacin and ciprofloxacin, respectively (95% CI, -4.1% to 24.5%); for pyelonephritis, the respective rates were 92% and 85% (95% CI, -20% to 37%). Clinical response rates of >90% were observed in both treatment groups among patients with complicated UTIs as well as those with pyelonephritis. Sustained eradication rates were 76% (64/84) with gatifloxacin and 66% (52/79) with ciprofloxacin. Both drugs were well tolerated, with the most common adverse events in both treatment groups being nausea, dizziness, diarrhea, and vomiting. CONCLUSIONS: Gatifloxacin is comparable to ciprofloxacin based on clinical efficacy and bacteriologic eradication rates for the treatment of complicated UTIs or pyelonephri- tis and is associated with a low incidence of clinically significant adverse events.