Mini Review: New Treatments in Psoriatic Arthritis. Focus on the IL-23/17 Axis.

Psoriasis, an inflammatory skin disease, and psoriatic arthritis (PsA), an inflammatory arthritis, share clinical, genetic, and pathogenic factors and may be summed as one disease, the psoriatic disease. Interleukin (IL)-17 plays a major role in the development of both psoriasis and PsA. IL-23 is important in the proliferation and maintenance of IL-17, and therefore, cytokines of the IL-23/IL-17 axis attracted much interest as therapeutic targets in psoriasis and PsA. Therapeutic agents targeting the IL-23/IL-17 axis have been proven to be very effective in psoriasis and PsA, some are already in the therapeutic armamentarium and others are in the development. Some agents, target IL-23 and others IL-17 and include anti-IL-12/IL-23 p40 (ustekinumab, briankizumab), anti-IL-23p19 (guselkumab, tildrakizumab, risankizumab, brazikumab, mirikizumab), anti-IL-17A (secukinumab, ixekizumab), dual anti-IL-17A and anti-IL-17F (bimekizumab), or anti-IL-17 receptor (brodalumab) monoclonal antibodies. Janus tyrosine kinase(JAK) inhibitors also directly affect IL-23 and, thus, IL-17. After the first-generation pan-JAK inhibitors have been shown efficacy (tofacitinib, baricitinib), new-generation selective JAK inhibitors (filgotinib, upadacitinib) are under investigation in psoriasis and PsA.