P667 Benefit of 5-ASA continuation on UC disease outcomes following initiation of a biologic

Abstract

Abstract Background In the era of advanced therapeutics for treatment of ulcerative colitis (UC) the benefit of routinely prescribed concomitant 5-aminosalicylate (5-ASA) compounds is still unclear. Methods A single centre, noninterventional retrospective cohort review study was performed on real-life data of adult patients with moderate-to-severe UC who were treated with biologics (infliximab, vedolizumab, ustekinumab) for a minimum of 6 months with or without concomitant use of 5-ASA. The difference in further treatment failure defined as a clinical negative composite outcome (need for steroid rescue therapy, biologic switch, IBD-related hospitalization and/or surgery) in two groups (5-ASA + biologic combination therapy vs biologic monotherapy) was assessed. Participants’ characteristics were assessed using descriptive statistics. Normal distribution was assessed using Kolmogorov-Smirnov and Shapiro-Wilk tests. Categorical variables were analysed using Chi-square test and continuous variables with Mann-Whitney test. Kaplan-Meier analysis and log-rank test were used in order to assess difference in therapy duration between two groups. Results Total of 104 patients (47.1% females; smokers 17.6%; concomitant stable dose oral 5-ASA 33%) were included. There were no differences in key baseline characteristics such as age, sex, smoking status, extraintestinal manifestations, serum albumin and CRP as well as fecal calprotectin levels between groups of patients receiving 5-ASA co-treatment and patients without 5-ASA. Median duration of therapy was 21 months (IQR 9-40). Concomitant use of 5-ASA was not associated with improved clinical outcomes; there was no statistically significant difference in the occurrence (χ2(1, N =102)=2.2, p=0.14) or time to develop (χ2(1, N =102)=1.12, p=0.29; Figure 1.) negative composite outcomes. Conclusion In our cohort we have failed to detect any benefit of 5-ASA continuation on significant clinical adverse events or hospitalisations in UC following initiation of a biologic.