A clinical trial and extension study of infliximab in Korean patients with active rheumatoid arthritis despite methotrexate treatment

Currently, infliximab is given for disease control for active rheumatoid arthritis (RA) patients despite methotrexate treatment. However, the efficacy and safety of infliximab in Korean patients has not been assessed appropriately. Therefore, we performed placebo-controlled, double-blind, randomized study and extension study. One-hundred forty-three patients with active RA were randomized to receive placebo or infliximab 3 mg/kg intravenously at week 0, 2, 6, 14, and 22 with methotrexate maintenance. Primary endpoint was American College of Rheumatology 20% improvement criteria (ACR20) at 30 week. After the clinical trial, patients on placebo (Group 1) and patients on infliximab who showed ACR20 response (Group 2) were treated with infliximab through another 84 week for evaluation of safety. During clinical trial, patients in infliximab group showed higher ACR20 at week 30 than patients in placebo group (50.1% vs 30.6%, P=0.014). A total of 92 patients participated in the extension study. The maintenance rate of infliximab was 62.0% at 84 weeks of extension study. The overall rate of adverse events was not different between Group 1 and Group 2. In Korean patients with active RA despite methotrexate treatment, infliximab in combination with methotrexate is effective and the long-term treatment with infliximab is well tolerated.