[Clinical efficacy and its influencing factors of vedolizumab in the treatment of ulcerative colitis].

<b>Objective:</b> To analyze the clinical efficacy and its influencing factors of vedolizumab (VDZ) in the treatment of ulcerative colitis (UC). <b>Methods:</b> The patients with moderately-to-severely active UC, who underwent VDZ treatment at the Second Affiliated Hospital of Wenzhou Medical University from November 2020 to November 2023 were retrospectively included. Based on whether 5-aminosalicylic acid (5-ASA) was used in combination with VDZ treatment, the patients were divided into combination group (received combination therapy of VDZ and 5-ASA) and monotherapy group (received monotherapy of VDZ). The clinical response rate and biological remission rate were analyzed at week 14. The clinical remission rate and mucosal healing rate were analyzed at week 38. The differences in efficacy of VDZ between the two groups were compared at week 14 and week 38, respectively. Multivariate logistic regression model was applied to analyze the influencing factors of clinical remission rate and mucosal healing rate in UC patients. <b>Results:</b> A total of 137 patients were included, including 74 males and 63 females, aged 18-76 (44±14) years old; Seventy-six cases in combination group and 61 cases in monotherapy group. At week 14 of VDZ treatment, the clinical response rate and biological remission rate were 79.6% (109/137) and 80.5% (33/41), respectively. At week 38, the clinical remission rate and mucosal healing rate were 78.8% (108/137) and 47.9% (57/119), respectively. There was no significant difference in clinical response rate and biological remission rate between combination group and monotherapy group at week 14 (both <i>P</i>>0.05). The clinical remission rate [85.5% (65/76) vs 70.5% (43/61), <i>P</i>=0.032] and mucosal healing rate [56.5% (39/69) vs 36.0% (18/50), <i>P</i>=0.027] were higher in combination group than those in monotherapy group at week 38. Multivariate logistic regression analysis showed that the combination therapy of VDZ and 5-ASA (<i>OR</i>=2.48, 95%<i>CI</i>: 1.02-6.03) and the clinical response at week 14 (<i>OR</i>=5.05, 95%<i>CI</i>: 1.98-12.85) were influencing factors of clinical remission rate of UC patients at week 38. Moreover, the baseline serum albumin (Alb) level ≥42.5 g/L was the influencing factor for the mucosal healing rate of UC patients at week 38 (<i>OR</i>=4.60, 95%<i>CI</i>: 2.06-10.24). <b>Conclusions:</b> VDZ is effective in treating UC patients. Both the combination of 5-ASA and the clinical response at week 14 are the influencing factors of the clinical remission rate at week 38. In addition, the baseline serum Alb level ≥42.5 g/L is the influencing factor of the mucosal healing rate at week 38.