The purpose of this study is to compare the safety and effectiveness of levofloxacin to ciprofloxacin in patients with chronic bacterial prostatitis.

Prostatitis (an inflammation of the prostate) is the most common condition affecting the urinary system in men under 50 years of age. Symptoms of chronic (long-term) prostatitis may include urgency to urinate, frequency or difficulty in urinating or abdominal, pelvic, or rectal pain. A frequent cause of prostatitis is bacterial infection, treatable with antibiotics. This multicenter, double-blind study evaluates the safety and effectiveness of levofloxacin as compared to ciprofloxacin in patients with chronic bacterial prostatitis. Patients receive treatment with either levofloxacin or ciprofloxacin for 28 days and are evaluated during treatment and 5-12 days after the last dose of study drug (posttherapy visit), and 1 month after the last dose (poststudy visit). Patients are contacted six months after the last dose to follow up on the potential recurrence of their prostatitis. Effectiveness is assessed by measuring the ability of the study drug to eliminate bacteria causing prostatitis and to reduce the signs and symptoms of chronic prostatitis. Laboratory tests for presence of bacteria are performed throughout the study and at each visit, patients are questioned as to the relief of their symptoms. Safety evaluations (incidence of adverse events, physical examinations, laboratory tests) are performed throughout the study. The study hypothesis is that levofloxacin is at least as effective as ciprofloxacin in treating chronic bacterial prostatitis without any significant safety issues being observed.

Levofloxacin 500 milligrams (mg) by mouth once daily or ciprofloxacin 500 mg by mouth twice daily for 28 days

Inclusion Criteria:

• Diagnosis of chronic prostatitis meeting all 3 of the following criteria: 1) clinical signs and symptoms of prostatitis including tender prostate and one or more of the following: difficulty in, frequency of, or urgency of urinating, retention of urine or hesitancy in urinating, decreased urinary stream, painful ejaculation, pelvic or low back pain, pain on examination, fever or chills
• 2) history of chronic prostatitis defined as 1 previous episode lasting 4 weeks or 2 or more episodes during the previous 12 months
• And 3) laboratory evidence of prostatitis
• Able to take oral medications
• Over-the-counter medications for chronic prostatitis are continued at the same dose during the study or are discontinued before study entry

Exclusion Criteria:

• Have taken an antibiotic similar to levofloxacin for any reason within the past 14 days
• Have received any medication for more than 24 hours during the past 7 days that may be effective in treating prostatitis unless there is evidence of treatment failure after 5 or more days of treatment with the other medication
• Have had certain surgeries during the past 6 months, including prostate surgery, surgical opening of the bladder or kidney or insertion of a permanent catheter (tube) for urination
• Taking any medications that may affect bladder or prostate