Treatment of rheumatoid arthritis with ornidazole: a randomized, double-blind, placebo-controlled study.

The aim of our study was to evaluate the clinical efficacy, safety, and tolerability of ornidazole in patients with rheumatoid arthritis (RA). This was 3 months, randomized, double-blind,placebo-controlled study. A total of 160 patients with active RA were randomly assigned to receive 1,000 mg ornidazole (n = 53), 500 mg ornidazole (n = 55), or placebo (n = 52). A significantly greater percentage of patients treated with 1,000 mg ornidazole met the American College of Rheumatology 20% improvement criteria (achieved an ACR20 response) at 3 months compared with patients who received placebo (62.0 vs. 32.4%; P < 0.001). Greater percentages of patients treated with 1,000 mg ornidazole also achieved ACR50 responses (38.3 vs. 10.9%; P < 0.001) and ACR70 responses (19.6 vs. 1.2%; P < 0.001) compared with patients who received placebo. Ornidazole treatment was also associated with significant reductions in pain and duration of morning stiffness, significant improvement in the quality of life and both the physician's and patient's global assessments, and significant reductions in disease activity as assessed by objective laboratory measures (erythrocyte sedimentation rate and C-reactive protein level). Ornidazole was well tolerated. There were no dose-limiting toxic effects. In this 3-month-trial ornidazole was safe, well tolerated, and associated with improvement in the inflammatory symptoms of RA.