EVALUATION OF THE EFFICACY AND SAFETY OF ETANERCEPT USE IN PATIENTS WITH NON-SYSTEMIC JUVENILE ARTHRITIS: 10-YEAR EXPERIENCE OF USE IN A FEDERAL CENTER

TNF-α inhibitors are used in the treatment of non-systemic variants of juvenile idiopathic arthritis (JIA) in case of ineffectiveness or intolerance to methotrexate. Despite 20 years of experience of using of etanercept in pediatric rheumatology, a long-term study of the efficacy and safety of the drug in real clinical practice remains necessary. Objective of the study: to study the efficacy and safety of etanercept for treatment of various non-systemic JIA subtypes in real clinical practice. Materials and methods of research: data from the case histories of 375 patients (242 girls and 133 boys) with articular forms of JIA for 2010–2020 were included in a retrospective, open, uncontrolled, nonrandomized, continuous multicenter cohort study. The age of debut was 6.3 (2.9; 10.7) years. Demographic characteristics, subtypes of arthritis, indicators of laboratory activity of inflammation, and outcomes were estimated: achievement of remission, exacerbation, and switching from etanercept to another genetically engineered biological drug (GEBD) were assessed. Results: remission was recorded in 78.9% on average after 6 months. The factors that determine the likelihood of achieving remission were the absence of previous therapy with GEBD (p=0.001) and compliance with therapy – OR=2.5 (95% CI: 1.3; 4.7), p=0.006. Exacerbations were recorded in 29.5% and were associated with the presence of the HLA B27 antigen – OR=2.6 (95% CI: 1.1; 6.0), p=0.028, antinuclear factor seropositivity (p=0.060). Change of etanercept to another GEBD was made in 17.4% of children and was associated with a failure to achieve remission – OR=7.7 (95% CI: 4.0–14.3), p=0.000001, with previous exacerbations – OR=14,8 (5.3; 41.2), p=0.0000001 and the development of de novo uveitis – OR=2.4 (95% CI: 1.1–5.3), p=0.038. The arthritis subtype and the presence of concomitant methotrexate therapy did not significantly affect treatment outcomes. Conclusion: achievement of remission, compliance with therapy, history of previous therapy with GEBD, exacerbation of JIA and development of de novo uveitis determined the main outcomes of etanercept therapy. The JIA subtype, as well as concomitant therapy with methotrexate, did not significantly affect the outcomes of the disease, which makes it possible to consider etanercept therapy a very effective and safe method of treating JIA as a genetically engineered first-line therapy of any variants of articular forms of JIA, even in monotherapy with ineffectiveness or intolerance to methotrexate.