Therapeutic efficacy and safety of methotrexate plus leflunomide in Colombian patients with active rheumatoid arthritis refractory to conventional treatment

Introduction: The combination of methotrexate (MTX) + leflunomide (LFN) has been shown to be effective in the treatment of RA. Its safety has been questioned. Objective: To evaluate the effectiveness and safety of the combination of MTX + LFN in patients with active RA. Methods: This was a 24-week multicenter study, which included 88 patients with active disease despite consistent treatment with methotrexate and prednisolone. Results: We included 78 women (88%) and 10 men. The age was 51.3 +/- 12.4 years, and the evolution of disease was 8 +/- 6.8 years. Patients had active disease, which was indicated by a median of IQR of 10.0 (7.0-13.0) for swollen and of 14.0(18.0-10.0) for tender joints for the whole group. The ACR responses achieved at week 24 were: ACR20: 76.0%; ACR50: 67.1%; ACR70: 23.9%. There was improvement in the activity of disease: DAS-28 score: 5.8 +/- 1.2 at baseline vs. 3.8 +/- 1.6 at week 24 (P = 0.000). The most significant adverse event was elevation of transaminases in eight patients (26%). Eight patients were withdrawn due to adverse events: four due to the elevation of transaminases, and one each due to diabetes insipidus, rash, diabetes mellitus and osteomuscular pain. Conclusion: The combination of MTX + LFN is effective for treating RA in patients for whom conventional treatment has failed. Strict medical and laboratory control is to be enforced for safety.