A Placebo-controlled Study With an Extension Examining the Safety and Efficacy of Alefacept in Psoriatic Arthritis

A Randomized, Double-blind, Placebo-controlled Study to Evaluate the Efficacy and Safety of Alefacept When Given in Combination With Methotrexate in Subjects With Psoriatic Arthritis With an Open-label Retreatment Course

Randomized, double-blind, 24-week study of patients with psoriatic arthritis comparing alefacept + methotrexate (MTX) vs. placebo + MTX followed by a 24-week open-label extension with only alefacept + MTX treatment.

Patients who completed the initial 24-week treatment course and met the inclusion and exclusion criteria for the 24 week open-label extension continued on their stable MTX dose and also received alefacept throughout this extension.

Inclusion Criteria:

• Psoriatic arthritis
• MTX treatment for 3 months prior to enrollment with continuing disease
• Normal T-cell count

Exclusion Criteria:

• Other types of psoriasis
• History of malignancy or lymphoproliferative disorder
• Serious infection or fever
• Antibody positive for Hepatitis C, HIV or TB
• Hepatic transaminases > 2X normal