Combination treatment with leflunomide and methotrexate in patients with rheumatoid arthritis: the efficacy, safety, and predisposing factors for treatment response

Chung, Seung Hie; Kim, Hak Jun; Kim, Sang Hyon; Kim, Chae Gi; Hwang, In Sun; Choe, Jung Yoon

Abstract

BACKGROUND: Leflunomide, a novel immunoregulatory drug, has been shown to be effective in rheumatoid arthritis (RA) as monotherapy and as combination therapy with methotrexate (MTX). The aims of this study were to investigate the efficacy and safety of combination therapy with leflunomide and MTX in active RA patients and to identify the patients with a better response to this combination.
METHODS
The patients received a maintenance dose of 20 mg of leflunomide with or without a loading dose. Parameters for disease activity in RA were measured at baseline and at 12 and 24 weeks after initiation of leflunomide. At 24 weeks, the baseline data from the patients classified as leflunomide responders were compared with data from nonresponders and analyzed to determine the potential predisposing factors for treatment response.
RESULTS
A total of 103 patients with RA were included and 93 (90.3%) patients received leflunomide for 24 weeks. At 24 weeks, 67 (65.1%) patients were DAS28 responders; 14 (13.6%) were good responders and 53 (51.5%) moderate responders. At 12 weeks, significant improvements were noticeable in the individual efficacy measures of diseases activity. There were also significant improvements between 12 and 24 weeks in swollen joint count, tender joint count, HAQ disability index, and patients' and physicians' global assessments of diseases activity; but no further improvements in ESR or CRP could be seen after the first 12 weeks. When comparing the baseline data from responders with the nonresponders, patients on a higher MTX dose and patients with a higher disease activity at baseline responded better to leflunomide. However, age, sex, disease duration of RA, functional status, loading dosage of leflunomide, and previous number of DMARDs used did not affect the patients' response to leflunomide.
CONCLUSION
Combination therapy with leflunomide and MTX is effective and safe across a wide range of patients, especially those with a high disease activity in spite of treatment with other traditional DMARDs.