Study To Evaluate Pf-04965842 In Subjects With Moderate To Severe Atopic Dermatitis

Inclusion Criteria:

- Male or female subjects between 18 75 years of age, inclusive, at time of informed
consent.

- Must have the following atopic dermatitis criteria:

1. Have a clinical diagnosis of chronic atopic dermatitis (also known as atopic
eczema) for at least 1 year prior to Day 1 and has confirmed atopic dermatitis
(Hanifin and Rajka criteria of AD refer to Appendix 2) at the Screening visit.

2. Have inadequate response to treatment with topical medications given for at least
4 weeks, or for whom topical treatments are otherwise medically inadvisable (eg,
because of important side effects or safety risks) within 12 months of the first
dose of study drug.

3. Moderate to severe AD (affected BSA >=10 %, IGA >=3, and EASI >=12 at the
screening and baseline visits).

Exclusion Criteria:

- History of human immunodeficiency virus (HIV) or positive HIV serology at screening,

- Infected with hepatitis B or hepatitis C viruses.

- Have evidence of active or latent or inadequately treated infection with Mycobacterium
tuberculosis (TB)

- Have received any of the following treatment regiments specified in the timeframes
outlined below:

Within 6 months of first dose of study drug: Any cell depleting agents Within 12 weeks of
first dose of study drug: Any studies with JAK inhibitors; Other biologics Within 8 weeks
of first dose of study drug: Participation in other studies involving investigational
drug(s) Within 6 weeks of first dose of study drug: Have been vaccinated with live or
attenuated live vaccine.

Within 4 weeks of first dose of study drug: Use of oral immune suppressants; Phototherapy
(NB UVB) or broad band phototherapy; Regular use (more than 2 visits per week) of a tanning
booth/parlor.

Within 1 week of first dose of study drug: Topical treatments that could affect atopic
dermatitis; Herbal medications with unknown properties or known beneficial effects for AD.