Background
Atopic dermatitis (AD) is a heterogeneous inflammatory skin disease with different clinical phenotypes based on factors such as age, race, comorbidities, and clinical signs and symptoms. The effect of these factors on therapeutic responses in AD has only been scarcely studied and not for upadacitinib. Currently, there is no biomarker predicting response to upadacitinib.

Objectives
Evaluate the efficacy of the oral Janus kinase inhibitor upadacitinib across patient subgroups (baseline demographics, disease characteristics and prior treatment) in patients with moderate-to-severe AD.

Methods
Data from phase 3 studies (Measure Up 1, Measure Up 2 and AD Up) were utilized for this post hoc analysis. Adults and adolescents with moderate-to-severe AD were randomized to receive once daily oral upadacitinib 15 mg, upadacitinib 30 mg or placebo; patients enrolled in the AD Up study received concomitant topical corticosteroids. Data from the Measure Up 1 and Measure Up 2 studies were integrated.

Results
A total of 2584 patients were randomized. A consistently greater proportion of patients achieved at least 75% improvement in the Eczema Area and Severity Index, a 0 or 1 on the validated Investigator Global Assessment for Atopic Dermatitis, and improvement in itch (including an achievement of a reduction of ≥4; and score of 0/1 in Worst Pruritus Numerical Rating Scale) with upadacitinib compared with placebo at Week 16, regardless of age, sex, race, body mass index, AD severity, body surface area involvement, history of atopic comorbidities or asthma, or previous exposure to systemic therapy or cyclosporin.

Conclusions
Upadacitinib had consistently high skin clearance rates and itch efficacy across subgroups of patients with moderate-to-severe AD through Week 16. These results support upadacitinib as a suitable treatment option in a variety of patients.