Effectiveness and safety of initiating adalimumab plus ≥12 mg/week methotrexate with adjustable dosing in biologic-naïve patients with early rheumatoid arthritis: HAWK study postmarketing surveillance in Japan

<b>Objectives:</b> This real-world study assessed the effectiveness and safety outcomes of initiating adalimumab and methotrexate (≥12 mg/week) with adjustable dosing in Japanese patients with early rheumatoid arthritis (RA). <b>Methods:</b> This single-arm, prospective postmarketing observational study (conducted from September 2012 to March 2017 at 119 sites) enrolled biologic-naïve patients with early RA (≤2 years duration) and a Disease Activity Score in 28 joints using C-reactive protein (DAS28-CRP) &gt;3.2 who were treated with methotrexate for ≥3 months and had initiated treatment with adalimumab and methotrexate (≥12 mg/week). This report presents 52-week data. The primary outcome was the proportion of patients who achieved DAS28-CRP scores &lt;2.6 at week 52. <b>Results:</b> Overall, 293 of 346 enrolled patients were included in the effectiveness population: women, 73%; mean (standard deviation) age, 54.3 (13.9) years; DAS28-CRP score, 4.51 (0.90); and modified total Sharp score (mTSS), 7.69 (9.98). At week 52, 77% of patients achieved clinical remission (DAS28-CRP &lt;2.6), 92.3% achieved low disease activity (DAS28-CRP ≤3.2), and 86% of evaluable patients experienced structural remission (ΔmTSS ≤0.5). <b>Conclusion:</b> Adalimumab plus methotrexate (≥12 mg/week) with adjustable dosing was well tolerated, and could be a beneficial treatment option for Japanese patients with early RA.