To review the effectiveness of systemic therapies for psoriatic arthritis (PsA).
Data on the efficacy of PsA therapies from selected literature, including American and international medical journals and recent abstracts from key rheumatology meetings, were reviewed.
Most therapeutic agents used to treat PsA are used on the basis of data from patients with rheumatoid arthritis (RA), and have not been adequately assessed in patients with PsA. However, the progressively destructive nature of the disease demands aggressive treatment with agents tested specifically in PsA. Conventional agents used to treat RA, such as methotrexate and sulfasalazine, have adverse effects that often lead to drug discontinuation and may not always be effective in reducing symptoms or radiographic progression in PsA. Newer medications, such as etanercept and infliximab, specifically inhibit the actions of tumor necrosis factor, which plays a major role in joint destruction. The Food and Drug Administration has recently approved etanercept for treatment of PsA. Current data with infliximab are limited to small open-label trials; however, randomized controlled trials are underway.
PsA and RA are distinct diseases, and the efficacy and safety of an agent in RA cannot necessarily be equated with efficacy and safety in PsA. For most conventional agents, data from controlled clinical trials in PsA are scant. Etanercept is currently the only therapeutic agent with sufficient data from placebo-controlled, randomized trials to receive a Food and Drug Administration indication for the treatment of PsA.