Abrocitinib is a Janus kinase-1 (JAK1)-selective inhibitor under investigation for the treatment of moderate-to-severe AD, inhibiting the activity of cytokines such as IL-4, IL-13, IL-31, IL-6, and interferons, which are critical in the pathogenesis of atopic dermatitis and other inflammatory diseases [15,16]. The gene discussed is JAK1; the disease is atopic eczema.