A Multicenter, Phase 3, Open-Label Study to Investigate the Efficacy, Pharmacokinetics, and Safety of Mirikizumab in Participants 2 Years to Less Than 18 Years of Age With Moderately to Severely Active Ulcerative Colitis

Inclusion Criteria: * Males or females weighing ≥10 kg and ≥2 and \<18 years old at the time of consent for screening. * Have moderate to severe UC. * Have failed corticosteroids, biologics, (for example, anti-tumor necrosis factor (TNF) antibodies or anti-integrin antibodies), immunomodulators (for example, azathioprine, thiopurines or methotrexate) or Janus Kinase (JAK)-Inhibitor treatment. * Have UC at least 3 months in duration before baseline, which includes endoscopic evidence of UC corroborated by a histopathology report. Exclusion Criteria: * Have Crohn's disease, Inflammatory Bowel…