Atopic dermatitis (AD) is a chronic, inflammatory cutaneous disease driven by immune dysregulation and skin barrier dysfunction. Currently, we are experiencing a new era of understanding of the pathogenesis of AD and, as a consequence, a new era of innovation in therapeutics, including small molecules and biologic therapy. In contrast to biologics, small molecules are similar to conventional pharmacologic chemical agents used as drugs and are generally prepared by chemical synthesis. Unlike biologics, these drugs often are taken orally or formulated for topical use. The purpose of this review is to summarize the efficacy and safety of the current topical and systemic new therapies in AD by reviewing recently published papers on therapies currently in phase 2 or 3 clinical trials. In this review, it is important to note the characteristics of the study population, the primary endpoints, and whether or not there was concomitant topical therapy allowed. These study design elements may significantly alter the results of studies and should be taken into account. Targeted therapy help push AD treatment into a new era of personalized medicine.

Atopic dermatitis (AD) is a chronic, inflammatory cutaneous disease driven by immune dysregulation and skin barrier dysfunction. We are currently experiencing a new era of understanding of the pathogenesis of AD and, as a consequence, a new era of innovation in therapeutics, including small molecules and biologic therapy. Recently, advances in translational research have challenged the traditional AD pathogenesis paradigm of AD being solely a Th2-dominant disease. Other immune pathways seem to play a role in the complex AD pathophysiology, although the clinical relevance of these additional immune pathway abnormalities is unclear. Type 1, type 22, and type 17 pathway activation (with related cytokines/chemokines) have been demonstrated in the skin and blood of AD patients. Type 2 (interleukin [IL]-4, IL-13), IL-31, and type 22 (IL-22) pathway cytokines are increased in AD acute lesions. IL-22 induces both an epidermal hyperplasia at the onset of acute AD and a marked increase in the terminal differentiation S100 genes.This understanding of pathogenesis corresponds to a historic increase in therapeutic development in AD. The extreme clinical heterogeneity and the chronic progression of AD establish the need for newer, safer, and more effective treatments, control the disease, and improve the quality of life of affected patients.