P870 Effectiveness and safety of adalimumab as first line biological treatment in Ulcerative Colitis

Abstract

Abstract Background The increase in licensed therapies for ulcerative colitis (UC) is revolutionizing its treatment but making first line choice more challenging. Adalimumab (ADA) is inexpensive but, anecdotally, is sometimes regarded as less effective than other first line advanced therapies. We aimed to evaluate the results of first line ADA in UC. Methods We performed a single centre retrospective analysis of UC patients started on ADA between January 15 and March 2022 in an IBD referral hospital. Clinical remission was defined as SCCAI <2 points, endoscopic remission as a UCEIS <2 points and treatment failure as the need for colectomy or second biological line Results A total of 79 patients were included (Table 1). Median follow-up was 19 months (2-91); 78.5% were followed >6 months. At 6 months, 80.3% (61/76) and 37.3% (22/59) of the patients were in clinical and endoscopic remission, respectively. 54.3% received combination treatment with immunomodulators (50.6% thiopurines, 3.7% methotrexate). Dose intensification to weekly treatment occurred in 27.8% after median 9 months (4-48 months). During follow-up 51% received corticosteroids at some point (26% topically-acting oral corticosteroids, 10% oral corticosteroids, 15% both). Of patients who received steroids, 55% (22/40) were able to continue adalimumab therapy. 2.5% of patients were hospitalised for a disease flare. 5.1% had an infection recorded during follow up, none discontinued the treatment. No other major adverse events were recorded. In 22.8% (18/79) of patients, ADA was stopped due to treatment failure, mean 15 months after starting the drug (4-56 months), (Figure 1). None of these patients underwent colectomy at the time of stopping the drug; in 17/18 a second biological therapy was started (10 tofacitinib, 1 filgotinib, 1 upadacitinib, 2 ustekinumab, 2 vedolizumab, 1 golimumab). TDM was performed using a drug-sensitive ELISA, which is only able to detect antidrug antibodies when drug levels are low or absent. Drug levels at the time of stopping the drug were <5 µg/mL in 22% of patients (in 2 antibodies were detected), 5-8 µg/mL in 11% and >8 µg/mL in 67%. Conclusion In a real-world UC cohort, ADA appears to be an effective well tolerated first-line advanced therapy with the vast majority of patients reaching clinical remission and a significant proportion achieving mucosal healing. Table 1. Cohort characteristics (N 79, frequency and %). Figure 1: Kaplan-Meier survival analysis of time to ADA discontinuation.