Novel treatments with small molecules in psoriatic arthritis.

Current treatment options for patients with active psoriatic arthritis (PsA) include synthetic disease-modifying antirheumatic drugs and biologic agents. Propelled by increased understanding of immunopathogenesis of PsA, new therapeutic agents targeting different biologic pathways have been evaluated. This article discusses novel small-molecule, orally available treatments that are currently in clinical development for the treatment of psoriasis and PsA. This includes the phosphodiesterase 4 inhibitor apremilast and Janus kinase (JAK) inhibitors. Apremilast has demonstrated significant improvements in patients with moderate to severe psoriasis and PsA in phase II and III clinical trials and has recently been approved for the treatment of PsA. Tofacitinib, an oral inhibitor of JAK3, JAK1, and, to a lesser degree, JAK2, approved for the treatment of rheumatoid arthritis in several countries, has demonstrated positive results in psoriasis in phase II studies. Studies in PsA are ongoing. With these new developments, treatment options will continue to improve in the future.