Ab0028 Long-Term Treatment Patterns of Canakinumab in Monogenic Autoinflammatory Diseases (Fmf, Traps, Hids/Mkd) and Systemic Juvenile Idiopathic Arthritis (Sjia) – 5-Years Data From a Belgian Registry

Background: Familial Mediterranean Fever (FMF), Hyper IgD Syndrome/Mevalonate Kinase Deficiency (HIDS/MKD), Tumor Necrosis Factor Receptor-associated Periodic Syndrome (TRAPS) and Systemic Juvenile Idiopathic Arthritis (SJIA, Still's disease) are autoinflammatory diseases causing serious burden to patients due to severe systemic and organ inflammation mainly caused by increased production of interleukin-1β (IL-1β). In clinical trials as well as in real-life, the human monoclonal antibody canakinumab (CAN) effectively inhibits IL-1β. CAN is approved and reimbursed for these indications, within the Belgian national healthcare system. Objectives: To describe patient demographics, quantitative use, dosing, and treatment discontinuations of CAN over 5 years in real-life in Belgium in FMF, TRAPS, HIDS/MKD and SJIA patients. Methods: This is a national, non-interventional, partly retrospective, and partly prospective registry of patients (from 2 years of age) who granted reimbursement and are treated with CAN in Belgium. The maximum observation period was 5 years (1 July 2018 to 30 June 2023). Results: 96 patients were included in 9 centers (54.2% female, 44.8% male, 12.5% Conclusion: In this Belgian cohort and during this observational period, most patients who received CAN suffered from FMF and only a small number suffered from TRAPS, HIDS/MKD and SJIA. From an epidemiological point of view, a higher number of cases with SJIA could be expected. The reimbursement criteria could have limited the number of patients receiving CAN. Only few patients (10.4% of total cohort) discontinued due to lack of efficacy and 2.1% (of total cohort) due to remission (both physician's judgement). CAN was initiated rather late in life (at mean 34.6 years) even though these syndromes mostly strike in childhood or young adulthood. Dosing overall was in line with the CAN Summary of Product Characteristics (SmPC). Weight-based dosing patterns, which is advised by the CAN SmPC REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests: Michel Moutschen: None declared, Hilde Rabijns Employee of Novartis, Carine Wouters: None declared.