Objective: To determine the effect of changing from etanercept or methotrexate (MTX) monotherapy to etanercept plus MTX combination therapy on radiographic progression in rheumatoid arthritis (RA) patients.
Methods: Patients enrolled in this 1-year open-label study previously completed a 3-year blinded study in which they received MTX or etanercept monotherapy or the combination of both. All patients received the combination of etanercept 25 mg subcutaneously twice weekly plus oral MTX up to 20 mg/wk. The primary radiographic endpoint was change in modified total Sharp score (TSS), as assessed by blinded readers.
Results: At baseline, patients previously receiving MTX monotherapy (ETN-added, n=52) or etanercept monotherapy (MTX-added, n=68) had moderate disease activity levels (mean disease activity score [DAS] of 2.6 and 2.5, respectively), whereas patients previously receiving combination therapy (Combination, n=90) had a low disease activity level (mean DAS of 2.0). Addition of etanercept to MTX monotherapy resulted in significant reduction in radiographic progression (P<0.05). Mean TSS changes in the previous year vs the current year were +1.79 vs +0.25 for the ETN-added group (p<0.05); +0.51 vs –0.18 for the MTX-added group (NS); and +0.42 vs +0.24 for the Combination group (NS).
Conclusion: In these RA patients with on average moderate disease activity despite previous MTX monotherapy, combination treatment with etanercept and MTX inhibited radiographic progression and improved radiographic outcomes. These data, in conjunction with the previously published clinical data, support the use of combination therapy in RA patients with moderate disease activity.