Introduction: Familial Mediterranean Fever (FMF) is a hereditary autoinflammatory disease that significantly reduces occupational productivity and quality-of-life in affected patients. Italy has an estimated FMF prevalence of 1 in 60,000 people. While colchicine is the primary treatment for FMF, biologics are administered to intolerant and non-responder patients. Anakinra and canakinumab are the only biologics approved and reimbursed for FMF in Italy. Both medicines have demonstrated efficacy in FMF patients yet differ in treatment costs. This study aimed to perform a budget impact analysis (BIA) following anakinra’s reimbursement for FMF treatment, considering pharmaceutical costs from the Italian National Healthcare Service (NHS) perspective. Methods: A ‘Reference scenario’ (all patients treated with canakinumab) was compared to an ‘Alternative scenario’, with increased anakinra market shares. The target population was estimated based on the Italian population, epidemiological and market research data. Drugs costs were estimated based on Summary of Product Characteristics and net ex-factory prices. Sensitivity analyses were implemented to test results’ robustness. Results:The base case analysis showed an overall cumulative expenditure of €30,586,628 for ‘Reference scenario’ and € 16,465,548 for ‘Alternative scenario’. A cumulative savings of €14,121,080 (46.2%) was calculated over 3 years as a result of the reimbursement and increasing uptake of anakinra. The sensitivity analyses, even considering a discount of 50% for canakinumab, confirmed the base case results. Conclusions: Anakinra’s introduction, in FMF treatment, provides a financially sustainable option for Italian patients, with savings increasing according to greater use of anakinra.