ASSESSING THE CLINICAL RELEVANCE AND RISK MINIMIZATION OF ANTIBODIES TO BIOLOGICS IN JUVENILE IDIOPATHIC ARTHRITIS (JIA) (ABIRISK) - PRELIMINARY RESULTS

Introduction: ABIRISK is a project funded by Innovative Medicine Initiative, with the aim to investigate anti-drug antibody (ADA) formation in the treatment of JIA with biologics (BPs). A major limitation to the use of biologics is the development of ADA that may decrease the efficacy of BPs. Objectives: The aim of this project is to improve the capability to predict biologic immunogenicity in JIA patients. Methods: JIA Patients (by ILAR criteria) followed by 24 PRINTO centres in 12 countries were prospectively enrolled and treated with Etanercept, Adalimumab or Tocilizumab. Patient’s data were obtained from Pharmachild, a pharmacovigilance data registry of JIA patients. For each patient detailed demographic and clinical information were reported; biologic samples were collected for PK and ADA detection before therapy start as well as at periodic visits up to month 18 of follow-up. Disease activity was assessed with Juvenile Arthritis Disease Activity Score-10 (JADAS10) and JIA American College of Rheumatology (JIA ACR) criteria. Results: 148 patients were included in the analysis. Five patients were considered twice because treated with 2 different sequential biologics. Demographic and clinical data by therapy are represented in the table. 54% of the patients were treated with Adalimumab. Disease duration was higher in the group receiving Tocilizumab. Disease activity showed a pattern of improvement over time both globally and for each treatment group (Table 1). Anti-adalimumab and antitocilizumab antibodies were detected respectively in 14 and 3 patients, while no patient developed antibodies anti-etanercept. Conclusion: Preliminary data show a global improvement of disease activity during follow-up period. Analysis of the correlation between drug concentration/ADA development and clinical information will help to determine which patients will respond best to which biologic.