Biologic therapies for the treatment of psoriatic arthritis

Psoriatic arthritis (PsA) is a chronic inflammatory rheumatic disease commonly associated with plaque psoriasis that, manifests with peripheral arthritis, dactylitis, enthesitis, and axial involvement. PsA can be progressive and harmful, resulting in joint deformities, functional impairments, low quality of life, and increased mortality. It was found that both non-pharmacologic and pharmacologic treatment could improve conditions of PsA. Recently launched biological products have become the main therapeutic agents used for treating PsA unresponsive to conventional disease modifying anti-rheumatic drugs. This paper aims at introducing available biologics for PsA management in Korea. The tumor necrosis factor-α inhibitor was the first approved biological product to show outstanding efficacy for treating PsA. Ustekinumab, designed for blocking interleukin-12/23, has been approved and widely used. Interleukin-17 inhibitors such as secukinumab and ixekizumab have also been introduced to improve the symptoms of PsA. It was found that many patients with PsA experienced a dramatic improvement in their condition after using these biological products. Additionally, new immunological modulators such as phosphodiesterase inhibitors and Janus kinase inhibitors were approved for the treatment of PsA.