To perform a Canadian multicenter randomized placebo-controlled trial to evaluate the safety and efficacy of 6 weeks of levofloxacin therapy compared with placebo in chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). Uncontrolled studies have supported the use of antibiotics in CP/CPPS.

Men with a National Institutes of Health (NIH) diagnosis of CP/CPPS (specifically, no infection localized to the prostate) were randomized to levofloxacin (500 mg/day) or placebo for 6 weeks in 11 Canadian centers. Patients were assessed at baseline and at 3, 6, and 12 weeks with the NIH Chronic Prostatitis Symptom Index (NIH-CPSI) and global patient assessments (subjective global assessment and patient assessment questionnaire).

Eighty men (average age 56.0 years, range 36 to 78; duration of symptoms 6.5 years, range 0.6 to 32) were randomized to receive levofloxacin (n = 45) or placebo (n = 35). All were evaluated in an intent-to-treat analysis. Both groups experienced progressive improvement in symptoms as measured by the NIH-CPSI. However, the difference in response was not statistically or clinically significant at end of treatment (6 weeks) or at the end of the follow-up visits (12 weeks). No patients withdrew because of adverse events. One patient withdrew before the 6-week assessment. Adverse events (all mild) were reported in 20% of the levofloxacin group and 17% of the placebo group.

This pilot placebo-controlled study showed that 6 weeks of levofloxacin therapy in men diagnosed with CP/CPPS resulted in symptom improvement that was not significantly different from that with placebo at end of treatment or follow-up. The clinical ramifications of these findings need to be addressed.