A Study of Mirikizumab (LY3074828) in Participants With Moderately to Severely Active Ulcerative Colitis

Inclusion Criteria: * Have an established diagnosis of UC for ≥3 months * Have confirmed diagnosis of moderately for severely active UC * Have current bowel urgency * Have demonstrated an inadequate response to, a loss of response to, or an intolerance to conventional or to biologic/Janus Kinase (JAK) inhibitor/sphingosine-1-phosphate (S1P) receptor modulator therapy for UC. Exclusion Criteria: * Have Crohn's disease (CD) * Have inflammatory bowel disease-unclassified, formerly known as indeterminate colitis, or * Have ulcerative proctitis, disease limited to the rectum, that is, distal to the recto-sigmoid junction, which lies approximately 10 to 15 centimeter (cm) from anal verge. * Have an inherited immunodeficiency syndrome or a monogenic cause of UC-like colonic inflammation * Have any history or current evidence of cancer of the gastrointestinal tract * Have active tuberculosis * Have HIV infection.