The role of IL-17 in the treatment of psoriatic arthritis.

Psoriatic arthritis (PsA) is a chronic inflammatory articular disease characterized by psoriasis, synovitis and enthesitis. Current treatment of PsA is mainly based on the use of classical and biological DMARDs; however, 30-40% of patients could not respond to these or have a loss of response. Areas covered: Recently, the discovery of new pathogenic mechanisms have made possible the development of new drugs that target the IL-17 with the possibility to interfere with the Th17 cells that are considered the cell type mainly involved in the development of the inflammation in PsA. New molecules have shown efficacy and safety over the various components of the disease in randomized clinical trials. These drugs have been recently approved for the treatment of PsA and included in the newest treatment recommendations. Other molecules are currently being tested in phase III clinical trials and are potential new treatment options for PsA. Expert Commentary: The aim of this paper is to review the role of IL-17 in the pathogenesis and treatment of PsA, with a discussion on the emerging anti-IL-17 drugs for PsA.