Feasibility of canakinumab withdrawal in colchicine-resistant familial Mediterranean fever.

Objectives: There is no consensus on canakinumab treatment tapering and discontinuation strategies in colchicine-resistant FMF patients. In this study, we aimed to establish a treatment management and discontinuation protocol in paediatric FMF patients treated with canakinumab.

Methods: Fifty-eight FMF patients treated with canakinumab were included. Since 2020, we have applied a protocol based on our experience whereby canakinumab is administered monthly in the first 6 months, followed by bimonthly for 6 months, and a final period of every 3 months (for 6 months). The patients were divided into two groups: 2012-2019 (group A) and 2020-2022 (group B).

Results: In group A (n = 33), the median duration of canakinumab treatment was 2.5 years [interquartile range (IQR) 1.9-3.7]. A total of 25 of 33 patients discontinued canakinumab after a median of 2.1 years (IQR 1.8-3.4). In two patients, canakinumab was restarted because of relapse. In group B (n = 25), canakinumab was discontinued in 18 patients at the end of 18 months. After a median follow-up of 0.8 years (IQR 0.6-1.1), two patients had a relapse and canakinumab treatment was reinitiated. The remaining 16 patients still have clinically inactive disease and are receiving only colchicine. When we compared the characteristics between groups A and B, there were no significant differences regarding demographics, clinical features, and outcomes.

Conclusion: This is the largest study in the literature suggesting a protocol for discontinuing canakinumab in paediatric FMF patients. It was possible to discontinue canakinumab successfully in more than half of the patients in 18 months. Thus we suggest that this protocol can be used in paediatric FMF patients.