The feasibility of withdrawing canakinumab in paediatric colchicine-resistant familial Mediterranean fever patients

To determine the feasibility of withdrawing canakinumab (CAN) in a large cohort of paediatric patients with colchicine-resistant familial Mediterranean fever (crFMF).This retrospective observational cohort study included paediatric crFMF patients that received CAN treatment for ≥6 months. Patient data were recorded at treatment onset (baseline), and at 1, 3, 6, 12, 18, and 24 months after initiation of treatment.The study included 114 patients that were followed-up for 2736 person-months. During the 24-month follow-up period, the CAN dose interval remained unchanged in 44 patients. The dose interval was extended in 58 patients within a median 6 months (range: 3-18 months) of treatment initiation. In all, 4 of these 58 patients had a new attack of crFMF after the dose interval was extended. CAN was withdrawn in 12 patients (in 5 at month 12 month and in 7 at month 18), of which 2 had a new attack within 3 months of withdrawal. In these 2 patients CAN was re-initiated with a dose interval of 8 weeks. The remaining 10 patients in which CAN was withdrawn did not report any symptoms throughout the remainder of the 24-month follow-up period. The median attack-free period in those treated with CAN was 669 d (95% CI: 644-696).The present findings show that it may be feasible to withdraw CAN or extend its dose interval in paediatric crFMF patients. Based on the present findings, we think that as the quantity of real-life data increases, standard CAN protocols may be developed.