P464 Effects of ozanimod on histologic remission and mucosal healing over 3 years of continuous treatment in patients with ulcerative colitis

Abstract

Background: Ozanimod is approved in the European Union, United States, and other countries for the treatment of moderately to severely active ulcerative colitis in adults (UC). The phase 3, randomised True North (TN) study demonstrated the efficacy and safety of ozanimod for up to 52 weeks in patients with moderately to severely active UC. The ongoing TN open‐label extension (OLE) aims to assess the long‐term efficacy and safety of ozanimod. This interim analysis of the TN OLE evaluated the efficacy of ozanimod on histologic remission (HR) and mucosal healing (MH) in patients who received approximately 3 years of continuous ozanimod treatment.Methods: In TN, patients were randomised to once‐daily ozanimod 0.92 mg (equivalent to ozanimod HCl 1 mg) or placebo (Cohort 1) or to open‐label ozanimod (Cohort 2) for a 10‐week induction period. Ozanimod clinical responders were rerandomised at Week 10 to oza‐nimod or placebo for a 42‐week maintenance period (MP). Patients with clinical response to ozanimod at Week 52 in TN were eligible to continue receiving ozanimod in the ongoing OLE. This interim analysis of the OLE (data cutoff: 10 January 2022, the point at which patient disposition was available for patients until OLE Week 94) included all patients on continuous ozanimod in the TN MP who achieved clinical response at Week 52 and enrolled in the OLE (n=131). Endoscopic and histologic endpoints were evaluated at OLE Weeks 46 and 94 (98 and 146 weeks of continuous ozanimod treatment, respectively) and reported using observed case analysis. Mean Mayo endoscopy scores were evaluated from TN baseline to OLE Week 94. Results: Of the 131 total patients included in this analysis, 87% completed OLE Week 46 (98 weeks of continuous ozanimod) and 72% completed OLE Week 94 (146 weeks of continuous ozanimod). Patients had a mean age of 44 years and 52% were female. Most patients (68%) had left‐sided UC, 69% had prior use of corticosteroids, 99% had prior use of 5‐aminosalicylic acid, and 32% had prior use of tumor necrosis factor inhibitors. Most TN Week 52 clinical responders achieved endoscopic improvement (EI), HR, and MH at OLE Weeks 46 and 94 (Figure 1). Ozanimod treatment was associated with a reduction in mean Mayo endoscopy score to 1.0 at TN Week 52; this was sustained through OLE Week 94 (Figure 2). Conclusion: In this interim analysis of the TN OLE, a large proportion of clinical responders after 1 year of ozanimod who remained on ozanimod for up to 2 years thereafter, achieved EI, HR, and MH after 2 and 3 years of continuous treatment. Long‐term ozanimod use may be associated with sustained endoscopic and histologic benefits in patients with UC. (Figure Presented).