Novel approaches for the treatment of psoriasis.

Psoriasis is a common skin disease affecting approximately 2% of the population. For those who contract the disease it is usually recurrent and sometimes very debilitating. The cause of psoriasis is unknown, although it appears to be an autoimmune disease with a likelihood for genetic predisposition. Past topical treatments such as emollients, coal tar and dithranol have been messy, cosmetically unacceptable and of low efficacy, while systemic therapies such as methotrexate, cyclosporin and acitretin have suffered from significant side effects. New therapies based on medicinal chemistry and an increased understanding of psoriasis have brought us closer to the goal of safe and efficacious treatment of the disease. The authors review some of these new topical and systemic therapies currently in use or in development.