Duration of etanercept treatment and reasons for discontinuation in a cohort of juvenile idiopathic arthritis patients

Since 2004, juvenile idiopathic arthritis (JIA) patients treated with etanercept and/or MTX have been monitored in the British Society for Paediatric and Adolescent Rheumatology Biologics and New Drug Register. Here, we report the duration of etanercept use for the first 5 years of the register and reasons for discontinuation. Disease subtype and activity, comorbidity, treatment efficacy and safety data were recorded. Etanercept discontinuation was defined as stopping the drug because of disease remission or treatment failure. Time to discontinuation was explored using Kaplan-Meier survival analysis with remaining patients censored at 5-year follow-up. A total of 483 etanercept-treated JIA patients were enrolled from 30 UK centres, representing 941 patient-years of follow-up. A total of 100 (20.7%) patients discontinued etanercept; 9 due to disease control, 88 because of treatment failure, 2 for unknown reasons and 1 because of a change in diagnosis. Of the 53 patients in whom etanercept was perceived to be ineffective at controlling the inflammation, 48 were prescribed other biologic drugs [26/48 (54%) infliximab]. In 21 patients with intolerance, infections, CNS events and a few isolated events were associated with discontinuation. Using Kaplan-Meier analysis, at 5 years 69% (95% CI 61, 77%) had not experienced treatment failure. Discontinuation of etanercept for inefficacy was associated with systemic arthritis subtype [odds ratio (OR) 2.55, 95% CI 1.27, 5.14], chronic anterior uveitis (OR 2.39, 95% CI 1.06, 5.35) and inefficacy of MTX before starting etanercept (OR 8.3, 95% CI 1.14, 60.58). In a cohort of JIA patients treated with etanercept and followed for a median of 2 years (maximum 5 years), the majority (69%) remain on the drug.