P462 Delayed Responders with Ustekinumab in Ulcerative Colitis Have Increased Inflammatory Burden but Similar Long-term Outcomes as Early Responders

Abstract Background Differences in one-year outcomes among early compared to delayed responders vedolizumab have been demonstrated ulcerative colitis. However, it is unclear whether differences exist with ustekinumab, and what factors differentiate from non-responders. Methods This was a post-hoc analysis of patient-level data the UNIFI clinical trial. Ustekinumab-treated patients response, defined as reduction total Mayo score ≥30% ≥3 points baseline rectal bleeding subscore (RBS)≥1 or RBS≤1, at week 8 were deemed their (week non-responders who subsequently responded 16). The primary outcome assessed remission (CR), ≤2 no >1. Other clinical, endoscopic, histologic also assessed. Outcomes using t-tests biomarkers one-way repeated measures variance. Results We included 642 ustekinumab-treated patients, including 321 (50%) responders, 115 (17.9%) 205 (32.1%) (Table 1). No observed for CR vs. [132/321 (41.1%) 40/115 (34.8%), p=0.233], nor any other 2). Similar findings regardless weight-based fixed ustekinumab induction dose 3). Compared had more severe endoscopic disease measured by MES [88/115 (76.5%) 206/321 (64.2%), p=0.015] likely abnormal CRP based on threshold > 3mg/L [83/115 (72.2%) 183/321 (57%), p=0.004]. non-responders, significant decline (F(4, 844), p<0.0001) fecal calprotectin 818), through 16 (Figure Conclusion greater inflammatory burden baseline. Early similar outcomes. Biomarker can be help them decision prolong initial should informed weighing overall risk benefit.