1. Subject with chronic (disease history of at least 6 months from diagnosis) moderate to severe plaque psoriasis involving the hands and/or feet (PGA - H&F ratings of 3 or 4) at screening, who have failed to respond to, or who have a contraindication to, or are intolerant to other systemic therapies including cyclosporin, methotrexate and PUVA. Subjects will be outpatients.