P1004 Proportion of agents for refractory ulcerative colitis and the efficacy of immunomodulator in 5-aminosalicylic acid intolerance

Abstract

Abstract Background 5-Aminosalicylic acid (5-ASA) is effective for ulcerative colitis (UC), yet several patients exhibit intolerance to this medication. Although biologics and immunomodulators are often employed in cases of 5-ASA intolerance in UC, reports on their induction rates and effectiveness are sparse. This study aims to ascertain the proportion of therapeutic agents for refractory UC and evaluate the efficacy of immunomodulators in patients intolerant to 5-ASA. Methods We conducted a retrospective chart review of 182 consecutive UC patients treated for refractory UC at our tertiary referral hospital from 2014 to 2023. The 5-ASA intolerance group comprised patients who initiated oral 5-ASA therapy, discontinued one or more oral 5-ASA treatments within 6 months due to adverse effects, and were unable to continue oral 5-ASA therapy for over 6 months. Those who had been on oral 5-ASA for more than 6 months were categorised as the 5-ASA tolerance group. We compared the types of agents for refractory UC (immunomodulators, calcineurin inhibitors, anti-TNF-α agents, vedolizumab, ustekinumab, JAK inhibitors), disease duration, and clinical background (age at diagnosis, history of acute severe UC [ASUC], disease extent) between the groups. Additionally, we examined the discontinuation rates due to adverse effects and the continuation rate of immunomodulators. Results Among the patients treated with agents for refractory UC, 19 belonged to the 5-ASA intolerance group and 163 to the 5-ASA tolerance group. The time to initiation of treatment for refractory UC was significantly shorter in the 5-ASA intolerance group compared to the 5-ASA tolerance group (median 69 days vs 1431 days, p < 0.001). The induction of immunomodulators occurred in 78.9% of the 5-ASA intolerance group, versus 38.0% in the 5-ASA tolerance group (p = 0.001). Anti-TNF-α agents was not used in the 5-ASA intolerance group, while 33.7% of the 5-ASA tolerance group received it (p = 0.001). 15 patients in the 5-ASA intolerance group and 53 in the 5-ASA tolerance group were introduced to immunomodulators to maintain remission. Discontinuations due to adverse effects were noted in 33.3% of the 5-ASA intolerance group and 18.9% in the 5-ASA tolerance group, but the differences were not significant. The one-year cumulative continuation rate of immunomodulators, excluding patients who discontinued due to adverse effects, was 93.3% in the 5-ASA intolerance group and 77.4% in the 5-ASA tolerance group, with no significant difference observed. Conclusion Immunomodulators are frequently introduced in cases of 5-ASA intolerance. No significant difference was found in the discontinuation rate of immunomodulators, with a high cumulative continuation rate observed in the 5-ASA intolerance group.