To Study the Use of Humanized CD25 in Preventing the Relapse of Psoriasis Vulgaris

Humanized anti-CD25 antibodies (anti-TAC), or placebo (saline solution), will be given as intravenous infusions on the following schedule: 2 mg/kg initially (maximum dose 200 mg) infusion given over 60 minutes, followed by a 1 mg/kg (maximum of 100 mg) infusion given over 30 minutes every two weeks thereafter for a total of 8 doses.

total body NB-UVB at a dose that is 50% of the MED. Patients are treated 3-7 times per week, with increasing doses at every treatment if no burning occurs. This is continued until for a total of 20 ± 2 treatments total.