MAP Study: Methotrexate and Adalimumab in Psoriasis

Assess the efficacy and safety of ADA compared to ADA/MTX in patients with psoriasis. Many studies of ADA in rheumatoid and psoriatic arthritis have allowed patients on stable doses of MTX to continue on MTX while being treated with ADA. There has been no prospective trial of MTX and ADA concomitantly in psoriasis. Safety of ADA monotherapy vs. combination ADA/MTX will be compared. Compare anti-ADA antibody formation and serum ADA levels in patients on ADA compared with those on combination ADA and MTX. ADA is a fully human monoclonal antibody to TNF-a. More recent advances in detection of ADA antibodies have shown that many patients develop antibodies to ADA while on treatment and some of these antibodies are neutralizing. The presence of anti-ADA antibodies has been correlated with loss of therapeutic response in many disease states.