AD is a disease that is fundamentally different from psoriasis, but also presents a high burden to patients, with severe interference in work capacity and ability to sleep. We are really just beginning to learn about AD, and there are currently no FDA-approved systemic drugs for the treatment of moderate to severe AD.
One topical treatment for AD is crisaborole, a phosphodiesterase 4 inhibitor that is likely to hit US markets in 2016. PDE4 increases intracellular cyclic AMP, which can have an anti-inflammatory effect. Phase 2 data for an IL-31 monoclonal antibody, nemolizumab, were reported recently. IL-31 is discussed a lot in the genesis of itch, but it is not just itch: IL-31 is critical to barrier integrity and to the generation of anti-microbial peptides; it is a pro-inflammatory cytokine. In some patients, blocking IL-31 appears to improve itch rapidly but there are a few side effects such as edema that will need to be monitored.