TYK2 and psoriasis: In addition, Deucravacitinib is the world’s first oral highly selective TYK2 inhibitor, which provides a novel targeted treatment option for severe erythrodermic psoriasis by precisely inhibiting pathogenic cytokine signaling such as IL-12/IL-23 through targeting and regulating TYK2 kinase in the JAK-STAT signaling pathway (53).