A single dose of anakinra for arresting familial Mediterranean fever attacks: a proof-of-concept study.

Objectives: Familial Mediterranean fever (FMF) is characterised by painful inflammatory bouts, typically lasting one to three days. Analgesics, the only available treatment to alleviate acute attacks, are often ineffective in reducing pain and attack duration. This study evaluates the efficacy of a single dose of anakinra, administered at the onset of FMF attack, in arresting the attack.

Methods: This prospective self-controlled case series involved patients receiving a single prefilled syringe with 100 mg anakinra for self-administration at attack onset. The primary outcome was the duration of anakinra-treated attacks compared to baseline attack duration. Additional attacks were treated with self-procured anakinra and analysed separately.

Results: Twenty-three attacks experienced by 23 patients and treated with the furnished anakinra were analysed. Treated attacks were arrested within 5.4±6 hours from anakinra administration, and lasted 8.33±6.8 hours from onset, significantly shorter than the 56.3±16.8 hours reported at baseline (p=0.0001). Use of purchased anakinra (43 injections by 6 patients) attained equal outcome. Early administration of anakinra (within ≤4 hours of attack onset) resulted in attack termination within ≤4 hours from anakinra injection in 17 of 20 (85%) and 37 of 41 (90%) of the attacks treated with furnished and procured anakinra, respectively. Adverse events were limited to one patient experiencing an injection site reaction.

Conclusions: Acute FMF attacks are highly responsive to early anakinra administration with low safety cost.