DOP030 Real-world effectiveness and safety of mirikizumab in refractory, biologic-experienced ulcerative colitis patients

Abstract Background Mirikizumab is the first selective anti-IL-23p19 monoclonal antibody available for moderate to severe ulcerative colitis (UC). Real-world data remain limited, and available evidence mostly derives from registration trials. Early observational studies suggest encouraging short-term efficacy, but data in biologic-experienced, refractory populations are scarce. Methods We conducted a prospective, observational, single-center study including UC patients treated with mirikizumab with a minimum follow-up of 12 weeks. Demographic data and previous therapies were collected. Clinical activity was assessed using the pMayo score at baseline, at week 12 (W12), and at 6 months (W24). Biomarkers and endoscopic activity (eMayo) were recorded according to clinical practice. Adverse events and need for colectomy were documented. Clinical remission was defined as pMayo