['ulcerative colitis']
['mirikizumab', 'placebo']

        Inclusion Criteria:

          -  Have moderate to severe active UC as defined by a Mayo score of 6 to 12 with an
             endoscopic subscore ≥2 within 14 days before the first dose of study treatment (note:
             a partial Mayo score of at least 4 and other eligibility criteria must have been met
             before endoscopy is performed as a study procedure)

          -  Have evidence of UC extending proximal to the rectum (≥15 centimeters [cm] of involved
             colon)

          -  Up-to-date colorectal cancer surveillance (performed according to local standard), for
             subjects with family history of colorectal cancer, personal history of increased
             colorectal cancer risk, age >50 years, or other known risk factor

          -  Participants must either: be naive to biologic therapy (eg, tumor necrosis factor
             [TNF] antagonists or vedolizumab) and have at least 1 of the following: inadequate
             response or failure to tolerate current treatment with oral or intravenous
             corticosteroids or immunomodulators (6-mercaptopurine or azathioprine) or history of
             corticosteroid dependence (an inability to successfully taper corticosteroids without
             return of UC) OR have received treatment with 1 or more biologic agents (eg, TNF
             antagonists or vedolizumab) at doses approved for the treatment of UC with documented
             history of failure to respond to or tolerate such treatment

        Exclusion Criteria:

          -  Have been diagnosed with indeterminate colitis, proctitis (distal disease involving
             the rectum only; less than 15 cm from the anal verge) or Crohn's Disease

          -  Have had surgery for treatment of UC or are likely to require surgery for UC during
             the study

          -  Have received any of the following for treatment of UC: cyclosporine or thalidomide
             within 30 days of screening, corticosteroid enemas, corticosteroid suppositories, or
             topical treatment with 5-aminosalicyclic acid within 30 days of screening
      