Immunologic Targets in Atopic Dermatitis and Emerging Therapies: An Update

Atopic dermatitis is one of the most common chronic inflammatory skin diseases. It usually begins in childhood, has a considerable impact on patients' quality of life, and incurs substantial healthcare costs. The standard-of-care treatments for patients with moderate to severe disease are very limited and have variable and typically insufficient efficacy and many side effects, some of which are quite serious. However, over the last decade, considerable advances in our understanding of the pathogenesis of atopic dermatitis have paved the way for a number of new treatments. Most notable are the drugs that target the Th2-polarized immune system, which is thought to play a key role in many of the signs and symptoms characteristic of this disease. In this article, we briefly review the pathophysiology of atopic dermatitis, while noting that each patient's disease phenotype is likely due to a unique interplay of several disease-specific dysregulated pathways. Lastly, we cover emerging therapies for atopic dermatitis, focusing on those that target specific components of the immune system, which are altered in atopic dermatitis. The hope is that these new biologics or small-molecule antagonists, which have high specificity for their target molecules, will decrease the undesirable side effects caused by off-target effects commonly observed with current immunosuppressive agents that are characterized by broad biological actions.