An Analysis of the Biological Disease-modifying Antirheumatic Drug-free Condition of Adalimumab-treated Rheumatoid Arthritis Patients

OBJECTIVES: The present study was performed with the aim of analyzing the biological disease-modifying antirheumatic drug (bDMARD)-free (Bio-free) condition of adalimumab (ADA)-treated rheumatoid arthritis (RA) patients in a real-world setting. METHODS: ADA was used in the treatment of 130 (male, n=21; female, n=109 females) RA patients. Among them, 26 patients (20.0%) discontinued ADA due to a good response. We analyzed 20 patients who were followed up for more than 6 months after the discontinuation of ADA. The Disease Activity Score 28 based on C-reactive protein (DAS28-CRP) and modified health assessment questionnaires (mHAQs) were evaluated. RESULTS: The mean age of the patients was 53.4±11.1 years. The mean disease duration was 4.5±4.3 years. Sixteen patients were bDMARD-naïve, while 4 switched from bDMARDs to ADA. At 6 months after the discontinuation ADA, 19 patients had achieved a clinical remission, and 1 had achieved a low disease activity. The Bio-free period was 26.4±15.5 months. The dose of prednisolone was significantly reduced from baseline (3.45±3.17 mg/day) at 6 months after the discontinuation of ADA (2.63±2.78 mg/day). The dose of methotrexate was unchanged. The number of conventional synthetic DMARDs (csDMARDs) was significantly increased (0.8±0.6 to 1.4±1.06). The mHAQ values were significantly ameliorated by ADA and remained good in patients with a Bio-free condition. A multivariate analysis showed that the dose of methotrexate (MTX) was an important factor for achieving a Bio-free condition. CONCLUSION: A sustainable Bio-free condition in a real clinical setting can be achieved and may be a suitable way of reducing medical costs. The dose of MTX and the additional administration of csDMARDs is therefore thought to be important for ensuring a good outcome in these patients.