Efficacy and safety of canakinumab for colchicine-resistant or colchicine-intolerant familial Mediterranean fever: A single-centre observational study

Objectives To evaluate the efficacy and safety of canakinumab in Japanese patients with colchicine-resistant or colchicine-intolerant familial Mediterranean fever (FMF) in a real-world clinical setting. Methods We reviewed 13 Japanese FMF patients to whom canakinumab was introduced during the period of October 2017 to December 2020. All patients were diagnosed as FMF according to Tel-Hashomer criteria. We performed genetic analyses for Mediterranean fever or MEFV by targeted next-generation sequencing. Efficacy was assessed by attack frequency and the percentage of patients who achieved attack improvement at 24 weeks. Safety was assessed by adverse events observed during canakinumab treatment. Results The median duration and follow-up of canakinumab treatment were 13 and 16 months, respectively. The median attack frequency was 0.50 [0.30-1.00] at 24 weeks, which was a significant decrease from 2.00 [0.85-2.88] at the time of induction (p = .019). There were three patients (23%) with complete resolution of attacks at 24 weeks. No serious adverse events were observed. However, one patient had small intestinal ulceration which led to the discontinuation of canakinumab. Conclusions Although the number of cases is small, this study suggests that canakinumab is efficacious and safe for use in Japanese patients with colchicine-resistant or colchicine-intolerant FMF in a real-world clinical setting in Japan.