We also reported the case of one patient with AOSD, treated with tadekinig alfa, whose high serum levels of free IL-18 became undetectable 2 h after the first subcutaneous administration of IL-18BP, remained low while in disease remission under therapy, and then increased when tadekinig alfa was discontinued, in parallel to AOSD relapse [64]. This evidence concerns the gene IL18 and adult-onset Still disease.