Outcomes and safety of tumor necrosis factor inhibitors in reactive arthritis: A nationwide experience from Iceland

Objective. Reactive arthritis (ReA) is a spondyloarthritis triggered by a bacterial infection. In cases where nonsteroidal antiinflammatory drugs and conventional synthetic disease-modifying antirheumatic drugs have failed, biologics such as tumor necrosis factor inhibitors (TNFi) have been used. However, limited evidence exists of the efficacy and safety of these drugs in ReA. We report on Icelandic patients with ReA who have been treated with TNFi, their characteristics, outcomes, and safety. Methods. We conducted an observational cohort study using the Icelandic nationwide database of biologic therapy (ICEBIO) supplemented with a retrospective study of electronic health record (EHR) data. Drug efficacy was assessed using disease activity scores and standardized questionnaires within ICEBIO; safety was assessed using ICEBIO and EHR data. Results. Thirty-eight patients with ReA were registered in the database. Eight were given TNFi within 1 year of symptom onset. At 6 and 18 months, there was a significant reduction in C-reactive protein (CRP), tender and swollen joints, visual analog scale for pain and fatigue, 28-joint count Disease Activity Score 28 based on CRP, Clinical Disease Activity Index, and Health Assessment Questionnaire scores. Seventy-one to 90% of patients were considered treatment responders. Two patients were able to stop biologics owing to remission. During the 303 patient-years (mean 8, range 1–15) biologics were given, 6 hospital admissions for infections were noted. Conclusion. TNFi are safe and effective in ReA, but treatment tends to be prolonged. Further clinical trials are urgently needed in ReA.