Clinical Response to Adalimumab Therapy and Its Determinants in Patients With Radiographic Axial Spondyloarthritis: A Prospective Real-World Study in Taiwan

AIM: To investigate the clinical response to adalimumab (ADA) in patients with active radiographic axial spondyloarthritis (r-axSpA) in Taiwan.

METHODS: In this real-world study, patients with r-axSpA, starting ADA therapy, were enrolled and followed up every 12 weeks for 48 weeks. Outcome parameters were the proportion of patients with an improvement of 50% in Bath ankylosing spondylitis disease activity index (BASDAI50), inactive disease (ID, < 1.3), and low disease activity (LDA, < 2.1) per ankylosing spondylitis disease activity score-C-reactive protein (ASDAS-CRP) and ASDAS-erythrocyte sedimentation rate (ASDAS-ESR), and change in peripheral and extra-musculoskeletal manifestations. Determinants of BASDAI50 response to ADA were examined. Treatment-emergent adverse events (TEAEs) were recorded.

RESULTS: Of 88 enrolled patients, 86 were analyzed, and 82 completed the study with all patients receiving 40 mg ADA fortnightly. Patients achieving BASDAI50 increased from 79.1% to 80.5% from weeks 12 to 48. At week 48, ASDAS-CRP and -ESR, ID, and LDA were improved from baseline in 60.8%, 74.7%, 42.1%, and 68.4% of patients, respectively. A decrease in enthesitis, peripheral arthritis, dactylitis, and uveitis was noted. Younger age, presence of uveitis, and use of conventional synthetic disease-modifying antirheumatic drugs were the determinants of treatment response. At least one TEAE was reported in 22.7%, serious AEs in 2.3% of patients, and no deaths. The most common TEAEs were upper respiratory tract infection (5.7%) and cough (3.4%).

CONCLUSIONS: This real-world, prospective study in Taiwan involving patients with active r-axSpA shows that ADA treatment effectively reduced disease activity and improved physical function. No new safety concerns were noted.