Granulomonocytapheresis for chronic inflammatory diseases and sepsis

Granulomonocytapheresis (GMA) has long been used to treat refractory chronic inflammatory diseases. Recently, an exploratory clinical study showed that GMA was effective for sepsis, and its use has been approved in Japan. The purpose of this review is to spread the knowledge about GMA in chronic and acute inflammation. GMA is a selective extracorporeal therapy designed to remove activated granulocytes and monocytes, key drivers of inflammation in various immune-mediated diseases. Initially developed for ulcerative colitis, GMA has since demonstrated immunomodulatory effects in conditions such as Crohn's disease, rheumatoid arthritis, and dermatologic disorders, by depleting activated myeloid cells and altering cytokine profiles, reducing tumor necrosis factor (TNF)-α, interleukin (IL)-6, and increasing IL-10. GMA aims to restore immune homeostasis without the systemic immunosuppression associated with pharmacologic agents. Recently, its application has expanded to critical care settings. In sepsis and cytokine storm syndromes, where overwhelming innate immune activation leads to organ dysfunction, GMA may offer therapeutic benefit. Preclinical models and pilot studies in septic patients suggest that GMA can reduce inflammatory mediators, improve hemodynamics, and support organ recovery. Reflecting this potential, GMA was approved for insurance reimbursement in Japan in August 2025 as adjunctive therapy for sepsis with systemic inflammation. Although GMA is a promising therapy for specific patients, there is limited supporting data, and its effect should be proven in future trials.