The ultra-rare skin disease X-linked hypohidrotic ectodermal dysplasia (XLHED) can be a heavy burden for children, affecting structures in the skin including sweat glands, respiratory glands, and hair as well as teeth. Though lacking a specific treatment to date, a pivotal clinical trial planned by the Geneva-based nonprofit Esperare Foundation and Pierre Fabre SA could now help bring one about.

Two Janus kinase (JAK) inhibitors, Abbvie Inc.'s Rinvoq (upadacitinib) and Pfizer Inc.'s Cibinqo (abrocitinib), have won U.S. FDA approvals for the treatment of people with moderate to severe atopic dermatitis. Reviews of both products for the indication were delayed due to FDA concerns about class risks. Accordingly, each is labeled with a boxed warning regarding risks of serious infection, mortality, malignancy, major adverse cardiovascular events and thrombosis.