This was 6-month, monocentre, randomized, double-blind, placebo-controlled study. We treated 100 patients with rheumatoid arthritis with either once-daily oral roxithromycin (300 mg) or daily oral placebo for 6 months. The primary efficacy variable was the percentage of patients who had a 20 percent improvement according to American College of Rheumatology (ACR) criteria (an ACR 20 response) at six months. Secondary outcome measures were 50 percent improvement and 70 percent improvement according to ACR criteria (an ACR 50 response and an ACR 70 response, respectively).