New and Emerging Biologics for Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease that is characterized by complex pathophysiology involving both skin barrier dysfunction and aberrant type 2 inflammation/immune responses. AD can be a debilitating condition that drastically impairs quality of life, especially in patients with moderate-to-severe disease. Currently, topical therapies such as corticosteroids and non-steroidal immunomodulatory therapy provide limited efficacy for patients with moderate-to-severe AD; limitations include inadequate response, cutaneous toxicity from overuse, and poor tolerance due to stinging and burning. Historically, the development of targeted therapies has been challenging due to the complex and multifaceted etiology of AD. Recent progress in understanding the immunopathology of AD reinforces the development of newly targeted therapeutics. The successful launch of dupilumab, a monoclonal antibody targeting the interleukin (IL)-4 alpha receptor subunit, for AD in 2017 spurred the development of a number of biologics targeting novel cytokine and receptor targets that are now in phase II and III of development. This review aims to explore the rationale behind these novel biological therapies and to summarize current clinical studies of these agents.