PP4. Treatment prescribing patterns in a cohort of patients with JIA: data from the Childhood Arthritis Prospective Study

Abstract

Background: JIA is a heterogeneous disease, classified according to ILAR. Initial treatment of the various presentations is based largely on disease severity; IA injections for oligoarthritis, MTX for polyarthritis and systemic presentations. The recent licensing of biologic therapies for use in JIA has revolutionized treatment of the disease. It is not currently known what proportion of children who present with polyarthritis will require biologic therapy. Although not studied formally, it is also recognized that a proportion of children with oligoarthritis will also require systemic therapy to control symptoms. Aim(s): To describe prescribing patterns within a cohort of patients with new onset JIA over the first 3 years following presentation to rheumatology. Method(s): Children with at least 3 years of follow-up within the Childhood Arthritis Prospective Study (CAPS), a prospective observational inception study of inflammatory arthritis, were included. For analysis, children were placed into one of four groups based on physician-assigned ILAR category and number of active joints at first presentation (baseline): oligoarthritis (oJIA), polyarthritis (pJIA), systemic (sJIA) and enthesitis-related arthritis (ERA). Treatment exposure over 3 years was determined and categorized into NSAID, IA steroids, DMARD including MTX and biologics including adalimumab (ADA), etanercept (ETN), infliximab (INF) and tocilizumab (TCZ). Result(s): 712 children were included (406 oJIA, 221 pJIA, 42 sJIA and 43 ERA). Over a 3-year period, almost 100% of children with pJIA and 50% of children with oJIA went on to receive a DMARD. 46% with pJIA and 17% with oJIA also received a biologic. The most recent ILAR category among children with oJIA who subsequently received a biologic included 39% extended oJIA, 19% pJIA, 4% ERA, 11% other subtypes; 27% had persistent oJIA. All sJIA patients were treated with DMARDs, with 36% receiving biologics (7% ADA, 33% ETN, 33% INF, 13% TCZ, 13% unknown). 63% of ERA patients received a DMARD with 26% going on to receive a biologic drug. Conclusion(s): Over a 3-year period almost all patients with pJIA received treatment with MTX and almost 50% required biologics. A high proportion of children presenting with oJIA also received DMARDs and biologics, with many children receiving such treatments for persistent oJIA, despite the lack of clinical trial evidence for effectiveness in this subtype. Further studies on the effectiveness in this subtype should be undertaken to ensure appropriate use of advanced therapies in this population.