Pharmacodynamic Response to Deucravacitinib, an Oral, Selective, Allosteric TYK2 Inhibitor, in a Global, Phase 2, Randomized, Double-Blind, Placebo-Controlled Psoriasis Trial

Psoriasis, a chronic, immune-mediated, inflammatory disease, affects 2‒3% of the population. Tyrosine kinase 2 (TYK2) mediates cytokine signaling involved in adaptive [interleukin (IL)-12, IL-23] and innate (type-I interferons) immune responses; IL-23-driven T-helper (Th)17 pathways play a key role in chronic inflammation in psoriasis. In a phase 2 trial, deucravacitinib, an oral, selective, allosteric TYK2 inhibitor, reduced IL-23/Th17 and type-I interferon pathway expression in the skin of patients with moderate to severe plaque psoriasis, reductions that were accompanied by clinical improvement of psoriatic lesions.