Study to Evaluate PF-04965842 in Patients With Moderate to Severe Psoriasis

Inclusion Criteria:

1. Have a diagnosis of plaque psoriasis for at least 6 months prior to first study dose.

2. Have plaque type psoriasis covering at least 15% of total BSA at Day 1 (at the time
of the first study dose).

3. Have a PASI score of 12 or greater at Day 1 (at the time of the first study dose).

4. Be a candidate for phototherapy or systemic treatment of psoriasis (either naïve or
history of previous treatment).

Exclusion Criteria:

1. Currently have non plaque forms of psoriasis, eg, erythrodermic, guttate, or pustular
psoriasis.

2. 3. Have current drug induced psoriasis, eg, a new onset of psoriasis or an
exacerbation of psoriasis from beta blockers, calcium channel blockers, antimalarial
drugs or lithium.

3. Have received any of the following treatment regimens specified in the timeframes
outlined below:

Within 9 months of first dose of study drug:

• Ustekinumab (Stelara).

Within 12 weeks of first dose of study drug:

• Any experimental therapy for psoriasis or rheumatoid arthritis.

Within 4 8 weeks of first dose of study drug:

- Biologic therapies for psoriasis have discontinuation periods determined from
approximately 5x half life of the respective biologic:

- 4 weeks: etanercept (Enbrel).

- 8 weeks: infliximab (Remicade), adalimumab (Humira).

Within 4 weeks of first dose of study drug:

- Systemic treatments other than biologics that could affect psoriasis (eg, oral or
injectable corticosteroids, retinoids, methotrexate, cyclosporine, fumaric acid
derivatives, sulfasalazine, hydroxycarbamide (hydroxyurea), azathioprine).

- Phototherapy and psoralen plus ultraviolet A therapy (PUVA).

- Other - intramuscular gold, immunization with any live virus vaccination (eg,
FluMist), herbal medications.

Within 2 weeks of first dose of study drug:

- Topical treatments that could affect psoriasis (eg, corticosteroids, tars,
keratolytics, anthralin, vitamin D analogs, and retinoids).

- Phototherapy with ultraviolet B (UVB) (narrowband or broadband).