TNF-alpha Blockers in Psoriasis: Reassuring Safety Data
TNF-alpha inhibitors are rapidly becoming a first-line therapy for moderate to severe psoriasis vulgaris and psoriatic arthritis. Because TNF-alpha blockers such as etanercept, adalimumab, and infliximab are chronic therapies, it would be reassuring to see safety data proving that long-term use of these selectively immunosuppressive agents poses minimal risks. Fortunately, several recent studies have addressed this important question.[20-22]
A meta-analysis reviewed safety data from 20 randomized controlled trials with a total of 6810 adult patients with psoriasis vulgaris (n = 5427) or psoriatic arthritis (n = 1383); all of these patients had been treated with anti-TNF-alpha agents or placebo for at least 12 weeks. On the basis of this meta-analysis, the investigators found no statistically significant increase in overall infection risk or malignancy risk in TNF-alpha antagonist vs placebo groups over a mean follow-up period of 17.8 weeks.[20]
A smaller Dutch cohort study followed 162 patients with psoriasis vulgaris who were taking either etanercept or adalimumab over a mean treatment duration of 1 year (etanercept) or 0.9 years (adalimumab). During this time period, mean laboratory values, including complete blood counts and liver function tests, remained within normal range, raising the question of whether frequent laboratory testing is necessary.[21]
What's the Significance?
Previous meta-analyses have shown that patients with rheumatoid arthritis who took TNF-alpha inhibitors have a modestly elevated risk of developing infections and malignancies.[22] This observation, however, is limited by the fact that most of these patients were concomitantly using other immunosuppressive drugs such as methotrexate and prednisone: drugs that independently increase risks for infection and malignancy. In contrast, patients with psoriasis vulgaris and psoriatic arthritis typically use TNF-alpha inhibitors as monotherapy. This may in part explain why the risk for malignancy and opportunistic infections does not appear to be significantly elevated in patients with psoriasis who take etanercept or adalimumab. Hopefully, longer-term follow-up data will confirm this reassuring trend
