Background The results obtained with the novel biologic agents have increased the expectations of benefit of treatment of juvenile idiopathic arthritis (JIA), with disease remission being now the therapeutic goal in all patients. However, the assessment of remission has seldom been incorporated in clinical trials of biologics in JIA. Moreover, little information exists on the prediction of the efficacy of biologic medications.
Objectives To evaluate the proportion of children with JIA treated with etanercept (ETN) who achieved the state of inactive disease (ID) and to search for predictors of ID.
Methods The clinical chart of all consecutive JIA patients who were given ETN between 2002 and 2011, and had a follow-up of at least 6 months after ETN start were reviewed. The achievement of ID, defined by the Wallace criteria (J Rheum 2004;31:2290-4), was assessed at each visit from the start of ETN. The primary study outcomes were: 1) proportion of patients who had ID at last follow-up visit while still on ETN; 2) time to achievement of ID after ETN start. Predictors of treatment outcomes included demographic data, JIA subset, type of affected joints, medications received before and during ETN administration, and JIA activity measures at ETN start. The search for predictors was conducted by means of univariate and multivariate analyses.
Results A total of 187 patients were given ETN at the standard dose of 0.8 mg/kg/week in the study period. The disease duration at ETN start ranged from 3 months to 21.2 years (median 5.0 years). Fourteen patients had received ETN for less than 6 months or were lost to follow-up. In the remaining 173 patients, treatment duration from baseline to last follow-up visit ranged from 6 months to 10.5 years (median 2.4 years). At last follow-up visit, 87 (50.3%) patients had ID. The time to ID ranged from 2 months to 6.3 years (median 0.7 years). An age at disease onset <3.6 years and the lack of involvement of the wrist joint at treatment start were the strongest predictors of both the achievement of ID at last follow-up visit (adjusted odds ratio of 2.1 and 2.7, respectively, in logistic regression analysis) and a shorter time to the attainment of ID (adjusted odds ratio of 1.6 and 2.2, respectively, in Cox regression analysis).
Conclusions Around half of our children with JIA treated with ETN achieved ID. Early disease onset and lack of involvement of the wrist joint at treatment baseline were associated with a greater likelihood and rapidity of achieving ID
Wallace criteria for inactive disease (J Rheum 2004;31:2290-4).
Disclosure of Interest None Declared