A Study of Mirikizumab (LY3074828) in Participants With Moderate to Severe Ulcerative Colitis

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