Anti-IL1 Treatment in Colchicine-resistant Paediatric FMF Patients: Real Life Data from the HELIOS Registry

Objectives: FMF is a prototype of autoinflammatory diseases associated with excess IL1 production. Anti-IL1 treatments are the first-line alternatives in colchicine-resistant/intolerant FMF patients. We aimed to investigate the efficacy and safety of anti-IL1 treatment in paediatric FMF patients in our local [Hacettepe univErsity eLectronIc research fOrmS (HELIOS)] registry.

Methods: HELIOS is a web-based biologic drug registry for paediatric rheumatology patients. We have analysed the clinical features, disease activity parameters, treatment responses and safety outcomes in FMF patients treated with anti-IL1 agents.

Results: Forty paediatric FMF patients (34 continuous and six on-demand use) were included. Among the continuously treated group (61.7% female), the mean age at the start of colchicine was 5.55 (3.87) years. Age at onset of the anti-IL1 treatment was 11.47 (5.41) years with a mean follow-up duration of 3.87 (1.96) years. Apart from two, all patients had biallelic exon-10 mutations. We also gave anti-IL1 treatment on an on-demand basis in six patients. Anakinra was used as the first-line anti-IL1 treatment. During the last visit, six patients were treated with anakinra and 28 patients with canakinumab. Anti-IL1 treatment decreased the CRP levels and number and severity of the attacks. There were three hospitalizations reported due to mild infections. Eleven patients had local skin reactions, two patients had leucopenia with anakinra and one patient had thrombocytopenia with canakinumab. There was no malignancy or other severe adverse reactions.

Conclusion: Anakinra and canakinumab are efficient and safe alternatives in colchicine-resistant or -intolerant paediatric FMF patients. We also, for the first time, report on-demand use of anti-IL1 in paediatric FMF patients.