JAK inhibitors in the treatment of atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disorder associated with heterogenous presentation and often immense patient burden. Safe, targeted treatment options are currently limited. This focused review of the published literature, including clinical trial results, case reports, and abstracts, as well as presentations from scientific meetings and data from industry press releases, describes the use of topical and systemic Janus kinase (JAK) inhibitors in the treatment of AD. New topical JAK inhibitors include ruxolitinib (JAK1/2) and delgocitinib (pan-JAK). Ruxolitinib cream met all primary and secondary endpoints in phase 3 clinical trials for mild-to moderate AD with minimal treatment-emergent adverse events. Delgocitinib ointment was recently approved in Japan for pediatric and adult AD. Oral JAK inhibitors include baricitinib (JAK1/2), abrocitinib (JAK1-selective), and upadacitinib (JAK1-selective). All 3 met primary and secondary endpoints across numerous trials for moderate-to-severe AD. Treatment emergent adverse events were mainly mild to moderate and included acne, nausea, headache, upper respiratory tract infection, and to a lesser degree, herpes infection and selected laboratory abnormalities. JAK inhibitors hold great promise as the next generation of targeted AD therapy. While their outstanding efficacy is balanced by a favorable safety profile in clinical trials, real-world data are needed to better understand long-term safety, durability, and treatment success. (J Allergy Clin Immunol 2021;148:927-40.)