Efficacy and Safety of Interleukin-23 Inhibitors (IL-23i) in the Treatment of Inflammatory Bowel Disease in China: A Multicenter, Single-Arm, Prospective, Observational Real-World Study

Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), has shown greatly improved outcomes with biologic therapies. However, nearly half of patients still experience primary or secondary non-response to existing biologics. Interleukin-23 (IL-23), a member of the IL-12 cytokine family, plays a role in maintaining intestinal homeostasis but is also involved in the pathogenesis of IBD. IL-23 is a heterodimer composed of p19 and p40 subunits linked by a disulfide bond. Humanized monoclonal antibodies selectively targeting the IL-23 p19 subunit have emerged as promising therapies for IBD. Recently, selective IL-23p19 inhibitors-risankizumab (Risan) and mirikizumab-have been approved for the treatment of moderately to severely active CD and UC, respectively. In addition, these agents, along with guselkumab (Gus), are undergoing clinical trials for both CD and UC (guselkumab, gus, and mirikizumab for CD; guselkumab and risankizumab for UC). Guselkumab (Gus) and risankizumab (Risan), both targeting the IL-23 p19 subunit, have been approved in China for the treatment of CD, with guselkumab also approved for UC. However, data on the efficacy and safety of IL-23 inhibitors (IL-23i) in Chinese UC and CD patients remain limited, and evidence in Chinese IBD populations is lacking. This is a multicenter, single-arm, prospective, observational real-world study designed to evaluate the efficacy and safety of IL-23i in adult UC and CD patients in routine clinical practice in China.