P846 Impact of 5-ASA discontinuation in children with ulcerative colitis under biological therapy

Abstract

Abstract Background Mesalamine (5-ASA) is recommended as a first-line medication for inducing and maintaining remission in mild to moderate ulcerative colitis (UC), but indications regarding its use in children with moderate to severe disease treated with biologics are lacking. We aimed to evaluate whether discontinuing 5-ASA might impact the outcomes of children with UC treated with anti-TNFα. Methods Retrospective, single-center, case-control study of children with UC receiving anti-TNFα therapy between January 2018 and January 2023 and with a minimum follow of 6 months. Children who discontinued 5-ASA within six months from the biological therapy initiation were compared to those who continued mesalamine as maintenance therapy. Every 6 months, during a 2-year follow-up, major outcomes defined as disease flares, IBD-related hospitalization, surgery, need for step-up treatment were recorded. Results Ninety-eight children were included in the final analysis, 51 (52%) maintained 5-ASA and 47 (48%) discontinued 5-ASA. The 2 groups were comparable for all the baseline clinical and demographic characteristics. At 6 months, the cumulative incidence of major outcomes, acute severe colitis and need for step up treatment was significantly higher in children who discontinued 5-ASA (p < 0.05). Throughout the follow-up period, children who discontinued 5-ASA were at significant higher risk of hospitalization (Log Rank p=0.02), need for step up treatment (Log Rank p=0.02) and acute severe colitis (Log Rank p=0.003). Conclusion Our data suggest that 5-ASA discontinuation might have a negative impact on the clinical course of children with UC treated with anti-TNFα in terms of major outcomes. However, conclusive evidence regarding this matter requires prospective randomized trials.