Refractory Ulcerative Colitis Successfully Treated With a Combination of Granulocyte and Monocyte Apheresis and Mirikizumab: A Case Report

We report the case of a 42-year-old man with treatment-refractory ulcerative colitis (UC), complicated by steroid dependence, adverse effects of immunomodulators, and significant social limitations, including inability to be hospitalized or take oral medications. Granulocyte and monocyte adsorptive apheresis (GMA) was initiated as an induction therapy, followed by the addition of mirikizumab, an anti-IL-23p19 monoclonal antibody. This sequential combination therapy resulted in significant clinical improvement and endoscopic mucosal healing. A detailed breakdown of the clinical course, objective disease activity markers, and colonoscopic findings is provided to illustrate the rationale and effectiveness of this approach. This case suggests that a stepwise treatment strategy combining GMA and biologics may be effective in managing treatment-refractory UC with complex clinical backgrounds. To our knowledge, this is the first reported case demonstrating the effectiveness of combination therapy with GMA and mirikizumab in UC.