TSO for Plaque Psoriasis

Inclusion Criteria: * Males or females, 18 to 75 years old. * Diagnosis of stable plaque type psoriasis for at least 6 months prior to baseline * Baseline moderate to severe psoriasis, defined as both of the following: 1. Psoriasis covering a body surface area (BSA) ≥ 10%, and; 2. PGA ≥ 3, and; 3. PASI ≥ 12 Exclusion Criteria: * Patients who are currently taking or have taken in the past 30 days, for any reason, any medication that, in the opinion of the investigator, suppressed the immune response. This may include but is not limited to systemic steroids, azathioprine, methotrexate, cyclosporine, FK506, mycophenolate mofetil, mycophenolic acid, etanercept, adalimumab, infliximab, ustekinumab, cimzia, or any other biologic agent targeted to any cell or cytokine in the immune system. Patients who are on inhaled or ophthalmic steroids are allowed. * Patients who have demonstrated a primary lack of response to any one of the following biologic agents: etanercept, adalimumab, infliximab or ustekinumab. Patients who initially responded to one of these agents but subsequently lost response (secondary lack of response) are eligible for study entry; however, secondary lack of response to more than one of these agents will exclude the patient from study entry.