POS0085 EVALUATION OF DURATION OF CLINICAL REMISSION IN CHILDREN WITH NON-SYSTEMIC JUVENILE IDIOPATHIC ARTHRITIS AFTER WITHDRAWAL OF ANTI – TUMOR NECROSIS FACTOR - ALPHA THERAPY

Background: Juvenile idiopathic arthritis (JIA) is the most common and prevalent rheumatic disease in childhood which is based on a chronic autoimmune inflammation. Inactive disease and remission are now the primary treatment goal in JIA and biologics have been playing an important role to reach this objective. The biologics of the first choice for the treatment of non-systemic JIA are the Tumor Necrosis Factor - alpha (TNFα) inhibitors; on this therapy patients can achieve clinically inactive disease and long-term remission. Currently, little is known about when or how to stop TNFα inhibitors, when a good clinical response is achieved, and therefore no guidelines are available. Objectives: To estimate the length of clinical remission after discontinuation of treatment with TNFα inhibitors in patients with non-systemic juvenile idiopathic arthritis. Methods: A total of 393 patients with JIA who were treated with TNFα inhibitors at the Rheumatology Department of the National Medical Research Center of Children’s Health (Moscow, Russia) were screened for inclusion in this retrospective study. Patients were treated with etanercept 1 times a week, 0.8 mg per kg of body weight per dose, with adalimumab 24 mg/m2 body surface area administered every other week until the end of therapy.Treatment was terminated abruptly. Inactive disease was defined according to the preliminary criteria of Wallace et al.[1] Results: 77 patients (27—male, 50—female) with a mean age at diagnosis of 4 years (range 1–18 years) were included in the analysis. Of those, 69 of them discontinued TNFα inhibitors due to a long-term remission on treatment, 8 patients as a result of side effects, and there were excluded from our study.: allergic reaction (n = 5), development of uveitis (n = 1), alopecia (n = 1), recurrent infection (n=11).The clinical subtypes of JIA were RF-negative polyarticular JIA -28 (40,58%) oligoarthritis—38 (55,07%), enthesitis-related arthritis—3 (4,35%). TNFα inhibitors were started after a mean 46,43 (range 1–144) months of disease. The mean duration of therapy with TNFα inhibitors were 46,63 (range 10-113) months, with a mean duration of remission on medication 40,63 (range 6-107) months before withdrawal of TNFα inhibitors. 40/69 (57,97 %) patients did not develop a disease exacerbation and remained in long-term remission off medication—more than 24 months. Early flares, that is less than 6 months after termination of TNFα inhibitors, were observed in 4/69 (5,8%) patients. 29 (42,03%) patients restarted TNFα inhibitors after exacerbation, due to lack of improvement after no biological DMARDs. All patients in whom TNFα inhibitors were reinitiated responded satisfactorily. Conclusion: Among patients with JIA in whom TNFα inhibitors were discontinued after inactive disease was achieved, 57,97 % had disease in clinical remission more than 24 months after stopping anti-TNFα therapy. No association was observed between the duration of inactive disease prior to TNFα inhibitors cessation and the time to disease relapse. In addition, we also ob- served no correlation between the risk of flare and the length of anti-TNF α therapy after inactive disease was achieved. In our population, TNFα antagonists were withdrawn a median of 38 (4-107) months after inactive disease was achieved. Data from our experience with anti-TNF α agents in the treatment of JIA suggest that 57,97 % of patients can be successfully withdrawn from TNF α antagonists for at least 24 months. References: [1]Wallace CA, Giannini EH, Huang B, Itert L, Ruperto N, for the Childhood Arthritis and Rheumatology Research Alliance (CARRA), the Pediatric Rheumatology Collaborative Study Group (PRCSG), and the Paediatric Rheumatology Interna- tional Trials Organisation (PRINTO). American College of Rheumatology provisional criteria for defining clinical in- active disease in select categories of juvenile idiopathic arthritis. Arthritis Care Res (Hoboken) 2011;63:929–36. Disclosure of Interests: None declared.