Study To Evaluate The Efficacy And Safety Profile Of PF-06651600 And PF-06700841 In Subjects With Alopecia Areata

This is a Phase 2a, randomized, double blind, parallel group, multicenter study with an extension period. The study will have a maximum duration of approximately 113 weeks. This includes an up to 5 weeks Screening Period, a 24 week Treatment Period, a 4 week Drug Holiday (#1), an up to 12 month Single Blind (investigator open, sponsor open and subject blind) Extension Period, a 4 week drug holiday (#2), a 6 month Cross Over Open Label Extension Period and a 4 week Follow up Period.

Sex

All

Minimum age

18 Years

Maximum age

75 Years

Inclusion Criteria:

* Male or female subjects between 18 75 years of age, inclusive, at time of informed consent.
* Must have moderate to severe alopecia areata:

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 2 week of first dose of study drug: Topical treatments that could affect AA; Herbal medications with unknown properties or known beneficial effects for AA.

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