Long-Term Outcomes of an Infliximab-First Versus Vedolizumab-First Treatment Strategy in Biologic-Naïve Patients With Ulcerative Colitis.

Background: Although studies have compared on-treatment effectiveness of infliximab and vedolizumab in patients with ulcerative colitis (UC), there has been limited comparison of treatment sequencing and long-term patient-centred outcomes.

Aim: To compare infliximab-first and vedolizumab-first strategy in biologic-naïve patients with UC.

Methods: We conducted a retrospective cohort study in biologic-naïve patients with UC who were treated first with either infliximab or vedolizumab between 2015 and 2021 and followed over 30 months following initiation. Primary outcomes were the number of hospitalisations, corticosteroid courses and serious infections with either strategy (regardless of switch to alternative therapies) within 30 months. We matched the groups 1:1 through cardinality matching, and fit logistic and zero-inflated negative binomial models to compare outcomes.

Results: We included 181 patients (94 vedolizumab-first and 87 infliximab-first treatment strategy). Of these, 144 were matched 1:1. There was no significant difference in the incidence of IBD-related hospitalisations (incidence rate ratio [IRR], 1.98 [95% CI, 0.64-6.10]), corticosteroid courses (0.66 [0.38-1.15]) and serious infections (5.26 [0.62-45.45]), with comparable incidence of medication switches to alternative advanced therapies (1.08 [0.42-2.81]). At 30 months, there was no difference in proportion of patients in clinical remission (69.4% vs. 76.4%; p = 0.45) and endoscopic remission (55.6% vs. 65.3%; p = 0.36).

Conclusion: In patients with UC, long-term effectiveness and safety outcomes are comparable with infliximab-first and vedolizumab-first treatment strategies at 30 months. This can help to guide selection of treatment strategies in patients with UC.