A single-center clinical study on the combination of Five-flavor sophora flavescens enteric-coated capsules and vedolizumab in induction therapy for ulcerative colitis

Objective: The aim of this study was to evaluate the efficacy and safety of Vedolizumab (VDZ) combined with Five-flavor sophora flavescens enteric-coated capsules (FSEC) for induction therapy in Ulcerative colitis (UC). Methods: UC patients treated with FSEC and/or VDZ were enrolled and divided into combination group (VDZ+FSEC) and single drug group (VDZ). The primary end points were clinical and endoscopic response and remission rates at week 14 and week 52. Secondary end points were the 14-week corticosteroid withdrawal rate, the number of bowel movements, the number of bloody stools, improvement in inflammatory markers, and safety. Results: The clinical response rate (97.4% vs. 79.1%, P = 0.011, 95% confidence interval(CI) 4.1%, 32.8%) and endoscopic response rate (74.4% vs. 51.2%, P = 0.031, 95%CI 2.2%, 41.4%) at week 14 in the combination group were significantly higher than those in the single-agent group. PP analysis showed that the endoscopic response rate at week 52 in the combination group was significantly better than that in the monotherapy group (85.7% vs. 62.5%, P = 0.042, 95%CI 2.0%, 44.4%), but there was no significant difference in ITT analysis. At week 14, the number of bowel movements and hematochezia scores were significantly improved in the combination group and the monotherapy group, and the improvement in the combination group was more significant at early stage and multiple time points. There were no serious adverse reactions in the two groups. Conclusion: FSEC combined with VDZ demonstrated superior clinical response rates and endoscopic response rates, and had greater advantages in early improvement of hematochezia and defecation frequency, compared to VDZ monotherapy, with a favorable safety profile.