Safety and efficacy of levofloxacin 750 mg for 2 weeks or 3 weeks compared with levofloxacin 500 mg for 4 weeks in treating chronic bacterial prostatitis.

OBJECTIVE

To compare the safety and efficacy of levofloxacin 750 mg QD for 2 weeks or levofloxacin 750 mg QD for 3 weeks to levofloxacin 500 mg QD for 4 weeks in treating chronic bacterial prostatitis (CBP).

RESEARCH DESIGN AND METHODS

This was a randomized, multicenter, double-blind, noninferiority study. The primary efficacy end point was investigator assessment of clinical success in the modified intent-to-treat (mITT) population at post-therapy. National Institutes of Health-Chronic Prostatitis Symptom Index (NIH-CPSI) scores were utilized to evaluate subject-reported responses post-therapy.

RESULTS

A total of 241 subjects were enrolled. At post-therapy (test of cure [TOC]), clinical success rates for levofloxacin-treated subjects (750 mg QD for 3 weeks [64.9%, 48/74]) were noninferior to 500 mg QD for 4 weeks (69.3%, 52/75: 95% CI, -19.5%, 10.6%). Success rates with levofloxacin 750 mg QD for 2 weeks (63.0%, 46/73) were not noninferior to therapy with levofloxacin 500 mg QD for 4 weeks (95% CI, -21.5%, 8.9%) at TOC. At 3 and 6 months post-therapy, clinical success rates were clinically higher for the 500-mg, 4-week treatment group, and statistical analysis demonstrated both groups were not noninferior to standard therapy with levofloxacin 500 mg (95% CI, -32.5%, -0.6% for both 750-mg groups at 6 months). NIH-CPSI scores showed similar trends. Overall, adverse event (AE) rates were similar for the three treatment groups; however, discontinuation of therapy due to AEs was higher with the 750-mg dose (p = 0.02, and p = 0.13 for 750 mg, 2 weeks and 750 mg, 3 weeks versus 500 mg for 4 weeks, respectively). The main limitation of this study was that no bacterial cultures were required.

CONCLUSIONS

Higher doses for shorter durations were determined to be no worse than standard therapy with levofloxacin 500 mg for a longer duration at the TOC visit. However, at the 6-month follow-up visit, the levofloxacin 750-mg dose administered for either 2 weeks or 3 weeks was inferior to the standard therapy, suggesting that a longer duration of treatment may help extend the relapse-free interval in patients with CBP.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov, nct00402688.