Background Juvenile idiopathic arthritis (JIA) is a chronic rheumatic disease with onset before 16 years. According ILAR classification there are several categories based on number of joints, clinical and laboratorial features. Patients with JIA without systemic features who fall or not tolerated to methotrexate (MTX) or sulfasalasine (SSZ) usually treated by biologics, especially TNFα-inhibitors. Currently only 2 TNFα-inhibitors approved in JIA: etanercept and adalimumab (ADA).
Objectives The aim of study was to evaluate the efficacy of ADA in children with JIA without systemic features and ability to induce remission.
Methods In the retrospective observation study were included 53 children (67.9% girls) with active JIA without systemic features, who were resistant to previous therapy with MTX alone (or SSZ in enthesytis-related arthritis) or with combination with other non-biologic DMARDs and were treated with subcutaneous ADA injections every 2 weeks. The onset age was 3.9 (1.7–7.8) years, the interval between onset of JIA and start of ADA was 4.2 (0.3–15.2). Uveitis was detected in 32 (60.3%) patients. According number of active joints and clinical features all patients were divided into 3 groups: oligoarthicular course (OA) – 4 active joints or less, polyarthricular course (PA) – 5 active joints or more and enthesitis-related arthritis (ERA) with any active joints. We evaluated routine clinical and laboratorial test for JIA and ability and time to achieve inactive disease, according to C. Wallace criteria (2004).
Results Number of active joints (NAJ) and erythrocyte sedimentation rates significantly decreased, while levels of C-reactive protein, WBC, Hb and platelets still unchanged. In 12 months after start of ADA median of NAJ was equal 0. During the trial 44 (84.6%) patients reached the status of inactive disease (ID) according the C. Wallace criteria in median time 122.0 (36.5–220.0). We have not found any significant differences of initial JIA parameters between patients who achieved and not achieved status of ID. We have found differences in JIA groups in achievement ID: patients with OA similar to PA faster and frequently get into remission than patients with ERA (p=0.03, Log-Rank test, OA vs ERA). During the trial 26 (50.0%) have experienced the flare throw the median time 551.0 (317.0–809.0) days after 1st ADA injection. Patients with flare had less NAJ [1.0 (0,0; 2,0) vs 4.0 (1,0; 8,0), p=0.007]. The main predictors of JIA flare during the ADA trial were calculated with Cox-regression models: JIA duration ≥4 years before start of ADA (HR=2.4, p=0.055), presence of concomitant uveitis (HR=4.8, p=0.0008) and discontinuation of MTX (HR=3.2, p=0.19). During the trial 1 SAE was detected: disseminated tuberculosis in patient who received ADA near 3 years (unrecognized family contact).
Conclusions In our study the efficacy of ADA was shown. Further trials required for evaluation long-term outcomes.
Disclosure of Interest None declared