Abstract: Deucravacitinib (DEUC) is a highly selective allosteric tyrosine kinase 2 (TYK2) inhibitor, a member of the Janus kinase family. It specifically mediates the intracellular signal transduction of cytokines such as IL-12, IL-23, and type I interferons (IFN-I), and has been approved for the treatment of moderate to severe plaque psoriasis and active psoriatic arthritis. In recent years, DEUC has been used off-label for immune-mediated dermatological disorders and rheumatic diseases with inadequate response to conventional systemic therapies, including systemic lupus erythematosus, lichen planus, alopecia areata, and systemic sclerosis. This article systematically summarizes the available clinical evidence, discusses the efficacy, safety, and mechanism of action of DEUC in the above diseases, and provides a reference for clinical targeted therapy.

Key words: deucravacitinib, TYK2 inhibitor, psoriasis, psoriatic arthritis, systemic lupus erythematosus, lichen planus, alopecia areata, systemic sclerosis