LAUSR

To the Editor: Psoriasis is a chronic multisystemic inflammatory disease. Interleukin (IL)-23/T-helper (Th) 17 pathway, tumor necrosis factor-a, and many inflammatory cytokines are involved in the onset and development of psoriasis, and the discovery of biologic targets of relevant cytokines have modified the psoriasis treatment paradigm. Althoughbiologics are effective in treating such diseases, the applications are still limited. Thus, smallmolecule inhibitors (SMIs) have gained considerable attention among researchers, owing to the simplified synthesis processes, low-cost production, and the possibility of oral or topical administration. This article summarizes SMIs in clinical development and those approved for the treatment of psoriasis.