Abstract Background Ozanimod, an oral sphingosine-1-phosphate (S1P) receptor modulator, is approved for moderate-to-severe ulcerative colitis. Although pivotal trials have demonstrated its efficacy, prospective real-world evidence in East Asian populations remains limited. This study aimed to evaluate the clinical, endoscopic, and biochemical outcomes of ozanimod in routine practice using a prospective multicenter cohort in Korea. Methods We conducted a prospective observational study across three Korean tertiary centers. Adults with moderate-to-severe ulcerative colitis who initiated ozanimod were enrolled and followed at predefined intervals. Clinical outcomes included stool frequency, rectal bleeding, Physician’s Global Assessment, and Partial Mayo score. Endoscopic activity was assessed using the Ulcerative Colitis Endoscopic Index of Severity (UCEIS). Biochemical parameters were collected at baseline, Week 10, Week 26, and Week 52. Data were summarized descriptively as mean ± standard error. Results Thirty patients were enrolled, of whom 24 (80%) were biologic-naïve and 6 (20%) had prior exposure to at least one biologic or small-molecule therapy. Clinical outcomes improved substantially after ozanimod initiation, with reductions in stool frequency, rectal bleeding, Physician’s Global Assessment, and Partial Mayo score evident by Week 10 and sustained through Week 52. Endoscopic activity, assessed by UCEIS, also decreased from baseline at early follow-up. Lymphocyte counts showed the expected decline after treatment initiation with partial recovery by Week 52. CRP and fecal calprotectin demonstrated overall improvement with variability related to limited sample availability. Liver function parameters (AST, ALT, and total bilirubin) remained stable without clinically meaningful deterioration. Adverse events were infrequent: one patient (3.3%) reported mild abdominal pain, and no serious adverse events or treatment discontinuations occurred. Conclusion In this prospective real-world multicenter cohort, ozanimod demonstrated meaningful clinical, endoscopic, and biochemical improvement in Korean patients with moderate-to-severe ulcerative colitis, with a favorable safety profile and no serious adverse events. These findings support the effectiveness and tolerability of ozanimod in routine clinical practice within an East Asian population. References: 1. Rubin DT, Dubinsky MC, Martino S, et al. Communications between physicians and patients with ulcerative colitis: reflections and insights from a qualitative study of in-office patient-physician visits. Inflamm Bowel Dis. 2017;43:494-501. 2. Koliani-Pace JL, Haron AM, Zisman-Ilani Y, et al. Patients perceive biologics to be riskier and more dreadful than other IBD medications. Inflamm Bowel Dis. 2020;26(1):141-146. 3. Vermeire SM, Gils A, Accossato P, et al. Immunogenicity of biologics in inflammatory bowel disease. Therap Adv Gastroenterol. 2018;1:1-13. 4. Taft TH, Ballou S, Bedell A, et al. Psychological considerations and interventions in inflammatory bowel disease patient care. Gastroenterol Clin North Am. 2017;46(4):847-858. 5. Wang Y, Parker CE, Feagan BG, MacDonald JK. Oral 5-aminosalicylic acid for maintenance of remission in ulcerative colitis. Cochrane Database Syst Rev. 2016;(5). 6. Danese S, Allez M, van Bodegraven AA, et al. Unmet medical needs in ulcerative colitis: an expert group consensus. Dig Dis. 2019;37(4):266-283. 7. Scott FL, Clemons B, Brooks J, et al. Ozanimod (RPC1063) is a potent sphingosine-1-phosphate receptor-1 (S1P1) and receptor-5 (S1P5) agonist with autoimmune disease-modifying activity. Br J Pharmacol. 2016;173(11):1778-1792. Conflict of interest: Mr. Kim, Dong Hyun: No conflict of interest Jin, Byung-Chul: nothing to declare Kim, Seong Jung: nothing to declare Kim, Hyun-Soo: No conflict of interest Kim, Sang-Wook: No conflict of interest Lee, Jun: Inflammatory bowel disease Colonoscopy
Kim et al. (Thu,) studied this question.