P0661 Efficacy of Upadacitinib in Isolated Small Bowel Crohn’s Disease: A Real-World Study

Abstract Background Patients with Crohn’s disease (CD) confined to the small bowel often show inadequate response to standard biologic therapies1. Real-world effectiveness data for upadacitinib, an oral, small-molecule Janus kinase (JAK) inhibitor, in this specific population remain limited. This study aimed to evaluate the effectiveness of upadacitinib in CD patients with isolated small bowel disease, utilizing the International Bowel Ultrasound Segment Activity Score (IBUS-SAS) as the primary objective assessment tool. Methods This retrospective study included 98 patients with active Crohn’s disease who received a 12-week induction therapy with upadacitinib (45 mg/day). Participants were stratified into two cohorts based on disease location: isolated small bowel CD (n = 40) and non-small bowel CD (n = 58). The primary endpoint was the change in IBUS-SAS at week 12 from baseline. Secondary endpoints included imaging, Crohn’s Disease Activity Index (CDAI), and relevant laboratory parameters, including C-reactive protein (CRP), heamoglobin (Hb), albumin (ALB), platelet count (PLT), and erythrocyte sedimentation rate (ESR). Both univariate and multivariate logistic regression analyses were employed to identify independent predictors associated with radiologic remission. Results At week 12, the rate of radiologic remissions were 30.0% in the isolated small bowel CD cohort vs. 36.2% in the non-small bowel CD cohort. There was no significant difference in the magnitude of IBUS-SAS and CDAI scores from baseline between groups (all p > 0.05) (Figure1), despite both achieving statistically significant reductions from baseline (all p < 0.05) (Figure2,3). Furthermore, the isolated small bowel CD group exhibited a significantly greater reduction in CRP and ESR compared to the non-small bowel CD group (all p < 0.05) (Figure4). Multivariate analysis identified previous intestinal surgery as an independent negative predictor of radiologic remission (OR = 0.287, 95% CI 0.094-0.877, p = 0.029) (Table1,2). Conclusion Upadacitinib induction therapy demonstrated comparable effectiveness in both isolated small bowel and non-small bowel Crohn’s disease populations. These findings support its use as a valuable therapeutic option for patients with Crohn’s disease confined to the small bowel. Reference: 1. TAKENAKA K, FUJII T, SUZUKI K, et al. Small bowel healing detected by endoscopy in patients with Crohn’s disease after treatment with antibodies against tumour necrosis factor [J]. Clin Gastroenterol Hepatol 2020;18:1545–1552. Conflict of interest: Ms. Xie, Shuyi: No conflict of interest Wu, Hongzhen: No conflict of interest Yao, Jiayin: No conflict of interest Zhi, Min: No conflict of interest Zhang, Min: No conflict of interest