Abstract Background Mirikizumab (MIRI), an anti-IL-23p19 monoclonal antibody, is approved for the treatment of ulcerative colitis (UC) and Crohn’s disease (CD). We present pooled safety analyses from Phase 3 clinical trials of MIRI in both UC and CD in order to better understand the MIRI long-term safety profile. Methods Data were pooled from adults with moderately to severely active UC (N = 1371; LUCENT-1, 2, and 3) or moderately to severely active CD (N = 1033; VIVID-1 and 2) who received treatment with MIRI for up to 4 years1, 2. In these pooled analyses, safety events were summarised for patients with UC or CD, and for both IBD indications combined. Data on safety outcomes were assessed by year of treatment and expressed in exposure-adjusted incidence rates (EAIRs), shown as rate of events per 100 patient years of risk (PYR). Results A total of 2404 patients (41. 4% females, median age 38. 0 years) were treated with MIRI across all IBD trials, for a cumulative 5967. 9 Patient Years of Exposure (PYE). The general safety profile was similar in adults with UC or CD. Among all IBD patients, treatment-emergent adverse events (TEAEs) occurred at a rate of 114. 6 events per 100 PYR, decreasing from 165. 3 events per 100 PYR to 79. 2 events per 100 PYR from year 1 to year 4 (Table 1). The observed rate of serious adverse events (SAEs) also generally decreased through Year 4 (Table 1). Incidence rates per 100 PYR for serious infections, major adverse cardiac events (MACE), malignancies, and hepatic events were consistent and low across 4 years of MIRI treatment, showing no increase with longer treatment exposure (Figure 1). Conclusion No new safety signals were found in this integrated analysis of data from Phase 3 clinical trials of MIRI in both UC and CD, with IR of safety events of special interest remaining stable through long exposure with MIRI. The safety profile of MIRI across the integrated IBD population through 4 years of treatment is favourable and consistent across both UC and CD indications. References: 1. Sands BE, D’Haens G, Clemow DB, et al. Three-Year Efficacy and Safety of Mirikizumab Following 152 Weeks of Continuous Treatment for Ulcerative Colitis: Results From the LUCENT-3 Open-Label Extension Study. Inflamm Bowel Dis. 2025;31 (7): 1876-1890. doi: 10. 1093/ibd/izae253 2. Barnes E, Sands BE, D’Haens G, et al. , LONG-TERM EFFICACY AND SAFETY OF MIRIKIZUMAB FOLLOWING 104 WEEKS OF CONTINUOUS TREATMENT FOR CROHN’S DISEASE: RESULTS FROM THE VIVID-2 OPEN-LABEL EXTENSION STUDY, Inflammatory Bowel Diseases, Volume 31, Issue Supplement₁, February 2025, Page S10, https: //doi. org/10. 1093/ibd/izae282. 024 Conflict of interest: Walsh, Alissa: Grant: Alfasigma, Helmsley Trust, Johnson & Johnson, Pfizer, Takeda Personal Fees: AbbVie, Alfasigma, Bristol Meyers Squibb, Dr Falk, Ferring, Johnson & Johnson, Lilly, Pfizer, Takeda, Tillotts Ferrante, Marc: Research grants from AbbVie, EG Pharma, Celltrion, Janssen, Pfizer, Takeda and Viatris Consultancy fees from AbbVie, AgomAb Therapeutics, Boehringer Ingelheim, Celgene, Celltrion, Eli Lilly, Janssen-Cilag, MRM Health, Merck Sharp and Dohme, Pfizer, Takeda and ThermoFisher Speakers’ fees from AbbVie, Biogen, Boehringer Ingelheim, Dr Falk Pharma, Ferring, Janssen-Cilag, Merck Sharp and Dohme, Pfizer, Takeda, Truvion Healthcare and Viatris Faye, Adam: Consulting/Educational funding from: AbbVie, Takeda, Eli Lilly Owen, Charles: Former Employee and Stockholder of Eli Lilly and Company Caldera, Freddy: r. Caldera has received research support from Novavax and Takeda Pharmaceuticals. He has been a consultant for Takeda, Arena Pharmaceuticals, GSK, and Celgene. Jairath, Vipul: Consulting Fees: Abbvie, Alimentiv, Amgen, Anaptys Bio, Asahi Kasei, Asieris, Astra Zeneca, Attovia, Blackbird Labs, BMS, Boehringer Ingleheim, Biomebank, Caldera, Calluna, Catalytic Health, Celltrion, Ensho, Enthera, Exeliome Biosciences, Ferring, Fresenius Kabi, Gilead, Granite Bio, GSK, Janssen, Lilly, Merck, Mountainfield, MRM Health, Nxera, Organon, OSE Immunotherapeutics, Pendopharm, Pioneering Medicine, Pfizer, Prometheus, Roche/Genentech, Sanofi, SCOPE, Shattuck Labs, Sorriso, Spyre, Synedgen, Takeda, Teva, Tillotts, Union Therapeutics, Ventus, Ventyx, Vividion, Xencor, Zealand Pharma. Pellanda, Paola: employees and shareholder of Eli Lilly and Company. Kaiser, Christopher: Employee and shareholder of Eli Lilly and Company Lopes, Michelle: I currently work at Eli Lilly as a Global Patient Safety Physician Todd, Kris: Employee and Stockholder of Eli Lilly and Company Durand, Frederick: Employee and Stockholder of Eli Lilly and Company Lee, Scott: S. L. reports grants and research support from AbbVie Inc, UCB Pharma, Janssen Pharmaceuticals, Inc, Salix Pharmaceuticals, Takeda Pharmaceutical Company, Celgene, Pfizer Inc, Atlantic Pharmaceuticals Ltd, Gilead Sciences Pty Ltd, Tetherex Pharmaceuticals, Arena Pharmaceuticals, and Shield Therapeutics PLC and consulting for UCB Pharma, Mesoblast Ltd, Cornerstone Pharmaceuticals, Janssen Pharmaceuticals, Takeda Pharmaceutical Company, Arena Pharmaceuticals, Eli Lilly and Company, Celgene, Celltrion, Pfizer Inc, and Salix Pharmaceuticals
Walsh et al. (Thu,) studied this question.