Study Evaluating the Mechanism of Action of PF-04965842 Monotherapy for Moderate-to-severe Atopic Dermatitis

A PHASE 2A, RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED, PARALLEL GROUP, MULTI-CENTER STUDY TO INVESTIGATE THE MECHANISM OF ACTION OF ABROCITINIB MONOTHERAPY IN ADULT PARTICIPANTS WITH MODERATE-TO-SEVERE ATOPIC DERMATITIS

B7451037 is a randomized, double-blind, placebo-controlled, parallel-group, Phase 2a study to investigate the mechanism of action of PF-04965842 by correlating efficacy outcomes with changes from baseline in key skin and blood biomarkers in adult participants at least 18 years of age with moderate-to-severe atopic dermatitis. Participants will be screened within 28 days prior to the first dose of study intervention to confirm eligibility. A total of approximately 51 participants will be randomized in a 1:1:1 ratio to receive PF-04965842 200 mg once daily (QD), PF004965842 100 mg QD, or matching placebo QD for 12 weeks. At the end of the 12-week study treatment, qualified participants will have the option to enter the long-term extension study B7451015 (NCT03422822). Participants discontinuing early from this study will undergo a 4-week off-treatment follow-up period.

Inclusion Criteria:

• Clinical diagnosis of chronic moderate-to-severe atopic dermatitis (AD) for at least 1 year
• Recent history of inadequate response to medicated topical therapy for AD or required systemic therapy to control disease
• Moderate-to-severe AD defined as affected BSA at least 10%, IGA at least 3, EASI at least 16, Peak Pruritus NRS at least 4

Exclusion Criteria:

• A current or past medical history of conditions associated with thrombocytopenia, coagulopathy, or platelet dysfunction
• Currently have active forms of other inflammatory skin diseases, i.e. not AD, or have evidence of skin conditions (e.g. psoriasis, seborrheic dermatitis, lupus) at the time of Day 1 that would interfere with evaluation of AD or response to treatment
• Participants who have received prior treatment with any systemic JAK inhibitors
• Require treatment with prohibited concomitant medication(s) or have received a prohibited concomitant medication within specified time frames prior to the first dose of study medication, including topical treatments that could affect AD
• Pregnant or breastfeeding women or sexually-active women of childbearing potential who are unwilling to use contraception