N27 The Journey to IL-23 Inhibitors in Inflammatory Bowel Disease: Real-World Experience from a UK Centre

Abstract Background Interleukin-23 (IL-23) inhibitors represent a new class in inflammatory bowel disease (IBD) therapy, with risankizumab and mirikizumab recently approved for Crohn’s disease (CD) and ulcerative colitis (UC), respectively. Real-world evidence on patient selection, sequencing, and early outcomes remains limited. We aimed to describe our early experience with IL-23 inhibitors and compare this with national and international data. Methods Data were collected prospectively from IBD patients initiated on risankizumab or mirikizumab between April 2024 and November 2025 at one of the largest UK NHS Trusts. Demographics, disease type, prior biologic exposure, immunomodulator history, steroid failure, baseline and 3-month biochemical (faecal calprotectin, FCP) and clinical activity scores, and safety data were recorded. Results were benchmarked against UK registry data and published real-world cohorts from Europe and North America. Results Fifteen patients were included (9 risankizumab, 6 mirikizumab). Mean age was 42 years; 60% had Crohn’s disease and 40% ulcerative colitis. All had failed ≥1 biologic, and 80% had failed ≥2 agents (infliximab, adalimumab, vedolizumab, ustekinumab, or upadacitinib). Seventy percent had prior immunomodulator use and 50% were steroid-refractory. Median baseline faecal calprotectin (FCP) exceeded 600 µg/g. Paired FCP data were available for only a minority at the time of analysis, precluding formal statistical testing; however, all available follow-up values demonstrated a downward trend consistent with early biochemical improvement. No significant adverse events were reported. Findings mirrored national and international trends, with comparable treatment exposure and early response rates. Conclusion Patients commencing IL-23 inhibitors are highly biologic-experienced with active disease. Early outcomes are encouraging and consistent with real-world data internationally. Longer-term follow-up will determine treatment durability and sequencing strategies. Conflict of interest: Scott, Glyn: No conflict of interest Preziosi, Giuseppe: No conflict of interest Barbara, Sissi: No conflict of interest Abreu, Beatriz: N/A