Objective: The aim of this study was to compare efficacy outcomes of initial treatment with adalimumab + MTX vs adalimumab addition following 26 weeks of MTX monotherapy in Japanese early RA patients naive to MTX with high disease activity.
Methods: Patients completing the 26-week, randomized, placebo-controlled trial of adalimumab + MTX were eligible to receive 26 weeks of open-label adalimumab + MTX. Patients were assessed for mean change from baseline in the 28-joint DAS with ESR (DAS28-ESR) and modified total Sharp score (mTSS), and for the proportions of patients achieving clinical, functional or radiographic remission.
Results: Of 333 patients assessed, 278 (137 from the initial adalimumab + MTX and 141 from the initial placebo + MTX groups) completed the 52-week study. Significant differences in clinical and functional parameters observed during the 26-week blinded period were not apparent following the addition of open-label adalimumab to MTX. Open-label adalimumab + MTX slowed radiographic progression through week 52 in both groups, but patients who received adalimumab + MTX throughout the study exhibited less radiographic progression than those who received placebo + MTX during the first 26 weeks (mean ΔmTSS at week 52 = 2.56 vs 3.30, P < 0.001).
Conclusion: Delayed addition of adalimumab in Japanese MTX-naive early RA patients did not impact clinical and functional outcomes at week 52 compared with the earlier addition of adalimumab. However, the accrual of significant structural damage during blinded placebo + MTX therapy contributed to the persistence of differences between the treatment strategies, suggesting that Japanese patients at risk for aggressive disease should benefit from the early inclusion of adalimumab + MTX combination therapy. Trial registration. ClinicalTrials.gov (http://clinicaltrials.gov/), NCT00870467.
Keywords: Japanese patients; MTX naive; adalimumab; rheumatoid arthritis; safety.