OP23 Efficacy and safety of upadacitinib as induction therapy in patients with Moderately to Severely Active Ulcerative Colitis: Results from phase 3 U-ACCOMPLISH study

Abstract Background Upadacitinib (UPA) is a selective and reversible Janus kinase inhibitor.U-ACCOMPLISH is one of two phase 3 induction trials that evaluated the safety and efficacy of UPA 45 mg once daily (QD) in adults with ulcerative colitis (UC). Methods U-ACCOMPLISH was a multicentre, randomized, double-blind, placebo-controlled trial (NCT03653026) that enrolled patients with moderate-to-severe UC (defined as adapted Mayo score 5–9 with centrally read endoscopic score 2–3) who had inadequate response, loss of response, or intolerance to aminosalicylates, immunosuppressants, corticosteroids and/or biologics. Patients were randomized 2:1 to UPA 45 mg QD or placebo (PBO) for 8 weeks. At week 8, responders entered the maintenance phase and non-responders entered the extended treatment period to receive open-label UPA 45 mg QD for additional 8 weeks.The primary endpoint (clinical remission per adapted Mayo Score) and ranked secondary endpoints including symptomatic, endoscopic– histologic evaluations from the 8-week PBO-controlled period are reported here. Non-responder imputation incorporating multiple imputation for missing data due to COVID-19 are reported. Results 522 patients were randomized (UPA, n=345; PBO, n=177); the intent-to-treat population included 341 patients in UPA and 174 patients in PBO group. Baseline demographics and disease characteristics were similar between groups; 50.7% and 51.1% were biologic inadequate responders in UPA and PBO groups, respectively (Table 1). A significantly higher proportion of patients receiving UPA 45 mg QD (33.5%) versus PBO (4.1%) achieved the primary endpoint (adjusted treatment difference: 29.0% [23.2, 34.7]; P Conclusion In U-ACCOMPLISH, 8-week UPA 45 mg QD induction treatment led to statistically significant improvements in clinical, endoscopic, and combined endoscopic-histologic endpoints. The treatment was well tolerated, and the safety profile and AE prevalence was comparable with previous studies of UPA with no new safety signals identified.