Correction of Psoriatic T Cell Signatures by Deucravacitinib

This study examines how deucravacitinib, a newer oral medication for moderate-to-severe psoriasis, restores abnormal immune cell patterns in the skin. Psoriasis involves overactive T cells — a type of immune cell — that drive inflammation. Deucravacitinib works by blocking a specific signaling pathway called TYK2, and researchers want to understand exactly how this reverses the harmful T cell signatures that cause psoriatic plaques. The study is open to adults aged 18 to 75 with moderate-to-severe psoriasis, defined as affecting at least 10% of body surface area, with a PASI score of 12 or higher and a physician's global assessment of 3 or above. People who are pregnant, breastfeeding, immunocompromised, have active serious infections or cancer, or have used systemic immunosuppressants in the past 12 weeks are excluded. Participants will receive deucravacitinib and provide skin biopsy samples at different timepoints for immune profiling. This research is important because it moves beyond simply measuring whether a drug reduces visible symptoms — it digs into the cellular and molecular machinery of the immune response, which could lead to better-targeted treatments and a deeper understanding of why psoriasis develops in the first place.