アトピー性皮膚炎治療の新時代　―新規薬剤の現状・可能性と課題について―

<p>Atopic dermatitis (AD) is a common, chronic inflammatory skin disease that is characterized by skin barrier dysfunction, inflammation and intense itch. Although the exact mechanisms behind its pathogenesis remain unclear, it is evident that the complex interplay among barrier dysfunction, inflammation and itch are critical in its development, progression and chronicity. Therefore, the treatment described in the current guideline are based on the pathogenesis of the disease: 1) topical anti-inflammatory therapy for inflammation, 2) moisturizer skin care for physiological abnormalities of the skin, and 3) search for and countermeasures against aggravating factors. However, in AD, itch is the most common problem for patients and its control is often very difficult. This may be due to the fact that the mechanism of itch in AD is very complex and probably differs from patient to patient.</p><p>With the discovery of key pathways responsible for the atopic skin inflammation and atopic itch, a new era in the treatment of AD began. Various substances involved in the pathogenesis of AD have been identified and many novel therapeutic agents targeting them are under development. New drugs currently employ two strategies of inhibiting specific key mechanisms in the pathogenesis of AD. The first strategy is based on inhibition of the type2 cytokines such as IL-13/IL-4 and IL-31. This group is represented by dupilumab and nemolizumab. The second strategy is based on reducing nonspecific inflammation using JAK-STAT inhibition. The already available baricitinib and upadacitinib, and upcoming abrocitinib are representative.</p><p>In this symposium I would like to discuss the clinical trial results of many new drugs, the action points of new drugs based on the pathogenesis of AD, their expected effects, and the experience of their use in clinical practice. In addition, I would like to discuss the future issues in the new era of treatment with many new drugs.</p>