Psoriatic Disease: Update on Traditional Disease-modifying Antirheumatic Drugs

We present an update on the effects of methotrexate (MTX), sulfasalazine (SSZ), leflunomide (LEF), and cyclosporine (CSA) in psoriatic arthritis (PsA) by reviewing data published from January 2010 to June 2014. The most relevant study on MTX, the Methotrexate In Psoriatic Arthritis (MIPA) trial, did not show a significant difference between this drug and placebo in improving peripheral synovitis. The trial, however, had several limitations. A cohort study on a small number of patients found that MTX does not inhibit radiographic progression. In a large observational study, 86% of LEF-treated patients met PsA Response Criteria (PsARC) at Week 24. No studies of sufficient relevance on SSZ were published in the examined time frame. In an open-label trial, CSA alone was compared to adalimumab (ADA) alone and to the combination ADA/CSA. The ADA arms showed a significantly higher response rate, but as many as 65% of CSA-treated patients were PsARC responders at Month 12. No relevant data on the effects of these 4 drugs on psoriatic enthesitis, dactylitis, or spondylitis have recently been published, and no new safety signals have been reported. Observational data from 2 registers suggest that concomitant MTX increases the retention rate of tumor necrosis factor-alpha inhibitors. The studies published in the examined time frame confirm that MTX, SSZ, LEF, and CSA have moderate symptom-modifying effect on psoriatic synovitis, and probably little effect on the other manifestations of PsA.