Comparative effectiveness of infliximab vs vedolizumab as first-line biologic therapy in moderate-to-severe ulcerative colitis: A prospective, multicenter, real-world study.

BACKGROUND: In real-world clinical settings, direct comparative evidence on the effectiveness of infliximab vs vedolizumab for biologic-naïve patients with moderate-to-severe ulcerative colitis remains limited. METHODS: This prospective, multicenter, real-world study enrolled patients with moderate-to-severe ulcerative colitis who were biologic-naïve and began using infliximab or vedolizumab from January 2023 to November 2024. To reduce confounding, inverse probability of treatment weighting was applied. The primary outcome was a composite of 14-week clinical remission and 52-week endoscopic remission. The secondary endpoints encompassed clinical response/remission, endoscopic response/remission, and clinical steroid-free remission at weeks 14 and 30; clinical remission, endoscopic remission, and clinical steroid-free remission at week 52; and the therapeutic continuation rate and adverse events rate across the complete observation period. RESULTS: In total, 251 eligible patients were enrolled. After inverse probability of treatment weighting, vedolizumab was significantly superior to infliximab for the composite endpoint (60.18% vs 39.52%; P = .003). Significantly greater proportions of patients in the vedolizumab group attained clinical remission (84.80% vs 66.49%; P = .003), steroid‑free clinical remission (75.87% vs 59.57%; P = .015), endoscopic response (70.43% vs 52.44%; P = .008), and endoscopic remission (70.43% vs 52.44%; P = .008) at week 14 relative to the infliximab group. Effectiveness endpoints were comparable between groups at week 30. At week 52, vedolizumab remained significantly superior in clinical remission (78.39% vs 57.38%; P = .003), clinical steroid-free remission (75.96% vs 53.39%; P = .002), and endoscopic remission (66.03% vs 51.12%; P = .042). The rate of adverse events did not differ significantly between the vedolizumab and infliximab groups (5.47% vs 7.57%; P = .56). CONCLUSIONS: Among patients with moderate-to-severe ulcerative colitis who have not been treated with biologics before, vedolizumab-first therapy showed superior short- and long-term effectiveness vs infliximab-first therapy, with comparable safety profiles. Vedolizumab could serve as the initial biologic agent for moderate‑to‑severe ulcerative colitis.NCT06962020; Selection and Efficacy-Inducing Factors of First-Line Biologic Agents in Moderate-to-Severe Ulcerative Colitis; https://clinicaltrials.gov/study/NCT06962020.