Clinical Significance of Endoscopic Improvement at 6 Months in Patients With Ulcerative Colitis Treated With...

Ustekinumab (UST), an anti-interleukin-12/23 p40 monoclonal antibody, has emerged as an effective therapeutic option for patients with moderate to severe ulcerative colitis (UC). However, early predictors of long-term treatment response remain unclear. This study aimed to assess whether 6-month endoscopic improvement (EI) predicts sustained clinical remission (CR) in patients with UC treated with UST.

This was a retrospective observational study performed at Kyorin University Hospital. Patients with active UC (Lichtiger Index ≥ 5) who began UST between June 2020 and July 2023 were included. CR was assessed using the LI at weeks 4, 8, 16, and 24. EI at week 24 and sustained CR at week 56 were evaluated.

Fifty-seven patients were enrolled, and the CR rate at week 24 was 57.9%. CR at week 4 was significantly associated with CR at week 24 (p = 0.004). Thirty-one patients underwent colonoscopy at week 24. EI was achieved in 11 patients (35.5%), and patients with EI versus without EI at week 24 showed significantly higher rates of sustained CR at week 56 (90.0% sensitivity, 100.0% specificity; p = 0.005). The UST continuation rate was also significantly higher in the EI group compared with non-EI patients (p = 0.04).

EI 6 months after UST initiation was associated with sustained CR at week 56. This finding highlights the importance of early endoscopic assessment in optimizing long-term outcomes in UST-treated UC.