Ulcerative colitis (UC) is a chronic inflammatory disorder of the large intestine. Data on the comparative effectiveness of biological therapies such as vedolizumab (VDZ) and ustekinumab (UST) remain limited. This retrospective study compared the effectiveness and safety of VDZ and UST in UC patients. Between November 2018 and November 2023, 106 patients were included: 64 received VDZ and 42 received UST. Bio-failure was significantly higher (p = 0.005) in the UST group versus the VDZ group. The remission rates at 6, 22, and 54 weeks in VDZ group were 51.6%, 61.3%, and 66.7%. The remission rates at 8, 24, and 56 weeks in the UST group were 66.7%, 65.0%, and 66.7%, respectively. Both treatments were comparable in inducing and maintaining clinical remission over 54–56 weeks, with no significant differences observed in the Lichtiger clinical activity index. Subgroup analyses highlighted the potential short-term effectiveness of UST among cases of bio-failure and a white blood cell level ≥ 9000/µL. Safety profiles were generally favorable, with no significant adverse events. Usutekinumab demonstrated effectiveness as a salvage therapy in patients who failed VDZ. Despite the increased disease severity in the UST group compared to the VDZ group, both groups demonstrated similar remission rates, suggesting UST shows significant efficacy even in moderate to severe UC.
