Objective: To evaluate the efficacy, including radiographic changes, and safety of etanercept and methotrexate (MTX), used in combination and alone, in patients with rheumatoid arthritis (RA) in whom previous treatment with a disease-modifying antirheumatic drug other than MTX had failed.
Methods: Patients with RA were treated with etanercept (25 mg subcutaneously twice weekly), oral MTX (up to 20 mg weekly), or combination therapy with etanercept plus MTX through a second year, in a double-blinded manner. Clinical response was assessed using American College of Rheumatology (ACR) criteria and the Disease Activity Score (DAS), in a modified intent-to-treat analysis with the last observation carried forward (LOCF) and in a population of completers. Radiographs of the hands, wrists, and forefeet were scored for erosions and joint space narrowing at annual intervals.
Results: A total of 503 of 686 patients continued into year 2 of the study. During the 2 years, significantly fewer patients receiving combination therapy withdrew from the study (29% of the combination therapy group, 39% of the etanercept group, and 48% of the MTX group). Both the LOCF and the completer analyses yielded similar results. The ACR 20% improvement (ACR20), ACR50, and ACR70 responses and the remission rates (based on a DAS of <1.6) were significantly higher with combination therapy than with either monotherapy (P<0.01). Similarly, improvement in disability (based on the Health Assessment Questionnaire) was greater with combination therapy (P<0.01). The combination therapy group showed significantly less radiographic progression than did either group receiving monotherapy (P<0.05); moreover, radiographic progression was significantly lower in the etanercept group compared with the MTX group (P<0.05). For the second consecutive year, overall disease progression in the combination therapy group was negative, with the 95% confidence interval less than zero. Adverse events were similar in the 3 treatment groups.
Conclusion: Etanercept in combination with MTX reduced disease activity, slowed radiographic progression, and improved function more effectively than did either monotherapy over a 2-year period. No increase in toxicity was associated with combination treatment with etanercept plus MTX.