Clinical pathophysiology of adult Still’s disease and the importance of IL-6 blockade for the disease management

Abstract

Adult Still’s disease（ASD）is a systemic inflammatory disease of unknown etiology, characterized by fever, rash and articular manifestations. The current concept of ASD includes a carry-over of systemic juvenile idiopathic arthritis（sJIA; disease onset < 16 years old）and adult（≥16 years old）-onset Still’s disease. The activation of macrophages and hypercytokinemia of interleukin（IL）-1β, IL-6 and IL-18 are crucial in the pathogenesis of ASD, and consequently, the efficacy of targeted therapies with biological agents against inflammatory cytokines has been demonstrated. In Japan, tocilizumab was approved for refractory ASD for the first time in the world in May 2019 according to the results obtained from an investigator-initiated multicenter clinical trial（KCCR-D002 study）.