Clinical, Functional, and Radiographic Benefits of Longterm Adalimumab Plus Methotrexate: Final 10-year Data in Longstanding Rheumatoid Arthritis

Objective. To examine the longterm effectiveness and safety of adalimumab in patients with longstanding rheumatoid arthritis (RA) and an inadequate response to methotrexate (MTX), and to assess the effect of a 1-year delay in initiation of combination therapy. Methods. DE019 was a 1-year randomized controlled trial (RCT) in which patients received adalimumab 20 mg weekly, adalimumab 40 mg every other week (eow), or placebo; all received concomitant MTX. Patients completing the RCT could receive open-label adalimumab 40 mg eow + MTX for an additional 9 years. Clinical, functional, and radiographic outcomes were assessed using composite measures of disease activity (e.g., American College of Rheumatology responses, 28-joint Disease Activity Score with C-reactive protein, Simplified Disease Activity Index), Health Assessment Questionnaire-Disability Index, and the modified total Sharp score (mTSS), respectively. Results. Of the 619 patients randomized, 457 entered the open-label extension; 202 completed 10 years. At Year 10, patients demonstrated effective disease control and inhibition of radiographic progression. Differences in clinical and functional responses between adalimumab + MTX and placebo + MTX observed during the RCT became less apparent at Year 10. Still, patients who initially received adalimumab + MTX had significantly lower mean Delta mTSS at Year 10 compared with patients who initially received placebo + MTX. No new safety signals arose following up to 10 years of adalimumab + MTX exposure. Conclusion. During up to 10 years of treatment with adalimumab + MTX, patients with longstanding RA experienced effective disease control with no change to the expected safety profile. A 1-year delay in receipt of adalimumab + MTX was associated with reduced effectiveness, suggesting that a window of opportunity to prevent irreversible damage exists even in a population with established RA.