Safety and efficacy of etanercept in children with the JIA categories extended oligoarthritis, enthesitis-related arthritis and psoriasis arthritis

The approval of etanercept for the treatment of the juvenile idiopathic arthritis (JIA) categories extended oligoarthritis (ExtOA), enthesitis-related arthritis (ERA) and psoriasis arthritis (PsA) was recently added to the approval for the treatment of polyarticular-course JIA (PA). This study aims to evaluate the efficacy and safety of etanercept in a large number of patients with the additional JIA categories. The Biologika in der Kinderrheumatologie (BIKER) registry documents baseline demographics, clinical characteristics and disease activity parameters. Efficacy was determined using the PedACR 30/50/70 response criteria and the Juvenile Arthritis Disease Activity Score (JADAS)-10. Safety assessments were based on adverse events’ reports. Until December 2012, a total of 1,678 JIA patients, incorporating 238 ERA, 315 ExtOA and 127 PsA patients were included. JADAS-10 demonstrated marked improvement compared to baseline after 3 to 24 months in ExtOA [16.1 ± 7.6 (baseline), 5.1 ± 5.2 (3 months), 3.0 ± 3.5 (24 months)]; ERA (15.3 ± 7.2, 4.4 ± 4.7, 4.0 ± 4.9) and PsA (14.7 ± 6.4, 5.0 ± 4.6, 5.3 ± 6.4). Compared to patients with PA, the rate of serious adverse events [relative risk (RR) 1.39 (0.95–2.03, p = 0.08)] and nonserious [1.18 (1.02–1.35; p = 0.03)] adverse events were elevated. The rate of uveitis flares was significantly higher in PsA (3.3/100 patient-years), ExtOA (2.8/100 patient-years) and ERA (2.7/100 patient-years) than in rheumatoid factor (RF)-negative polyarticular JIA (1.3/100 pat.yrs) or RF-positive polyarticular JIA (0.27/100 patient-years). Reports on chronic inflammatory bowel disease were numerically more frequent in ExtOA, ERA and PsA. Administration of etanercept in patients with the JIA categories ExtOA, ERA and PsA is safe and very efficacious in children. Attention should be paid to the occurrence of extraarticular autoimmunopathies.