A Study to Evaluate the Efficacy and Safety of Mirikizumab (LY3074828) in Participants With Moderate-to-Severe Plaque Psoriasis

Inclusion Criteria:

- Present with chronic plaque psoriasis based on an investigator confirmed diagnosis of
chronic psoriasis vulgaris for at least 6 months prior to baseline and meet the
following criteria:

- plaque psoriasis involving ≥10% BSA and absolute PASI score ≥12 in affected skin
at screening and baseline

- sPGA score of ≥3 at screening and baseline

- Candidate for systemic therapy and/or phototherapy for psoriasis.

Exclusion Criteria:

- Have an unstable or uncontrolled illness, including but not limited to a
cerebro-cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine,
hematologic, or neurologic disease or abnormal laboratory values at screening, that in
the opinion of the investigator, would potentially affect participant safety within
the study or of interfering with the interpretation of data.

- Breastfeeding or nursing women.

- Have had serious, opportunistic, or chronic/recurring infection within 3 months prior
to screening.

- Have received a Bacillus Calmette-Guerin (BCG) vaccination within 12 months or
received live vaccine(s) (including attenuated live vaccines) within 12 weeks of
baseline or intend to receive either during the study.

- Have any other skin conditions (excluding psoriasis) that would affect interpretation
of the results.

- Have received systemic nonbiologic psoriasis therapy or phototherapy within 28 days
prior to baseline.

- Have received topical psoriasis treatment within 14 days prior to baseline.

- Have received anti-tumor necrosis factor (TNF) biologics, or anti-interleukin (IL)-17
targeting biologics within 12 weeks prior to baseline.

- Have previous exposure to any biologic therapy targeting IL-23 (including
ustekinumab), either licensed or investigational.