Fifty-nine female patients with a history of at least three episodes of
urinary tract infection in the preceding year were enrolled in a two-center, double-blind study comparing
cinoxacin and placebo as preventive
therapy. Evaluation of efficacy was based on the results from 41 patients for whom complete data were available. In the
cinoxacin-treated group, 18 of 20 patients remained asymptomatic during the study, compared with 11 of 21 patients in the placebo group. This difference between the two treatment groups was significant (P = 0.031). One patient in the
cinoxacin group and eight patients in the placebo group developed an
infection during the study. This difference was also significant (P = 0.045). Nine patients spontaneously reported adverse reactions, four in the
cinoxacin group and five in the placebo group. In four instances, these were sufficiently severe for the treatment to be withdrawn from one patient who received
cinoxacin and three patients who received placebo. The results of this study have shown that
cinoxacin was significantly more effective than placebo in preventing
urinary tract infection in patients with a history of frequent
recurrent infections.