Abstract
Psoriasis is a chronic skin disorder that affects approximately 2% of the US and European populations. Over the last few years, one of the major focuses in psoriasis research has been the development of biological therapies for this disease. The aim of these therapies is to provide selective, immunologically directed intervention with fewer side effects than traditional therapies. The goal of this article is to update the progress of the tumor necrosis factor inhibitors that are available, or under investigation, for clinical use in psoriasis: infliximab, etanercept and adalimumab, as well as the T-cell-targeted therapies efalizumab and alefacept.