A Safety and Efficacy Study to Evaluate Efalizumab in Combination With UVB for Moderate to Severe Psoriasis

Inclusion Criteria: Subject has given informed consent Subject is in generally good health, and an ambulatory male or female adult (18 years or older) Subject has moderate to severe plaque psoriasis affecting greater than or equal to 5% body surface area Subject is a candidate for efalizumab in combination with narrowband UVB phototherapy in the opinion of the assessing investigator If a female of childbearing potential, a negative pregnancy test and commitment to the use of two forms of effective contraception (birth control) for the duration of the study are necessary If a non-sterile male, commitment to the use of two forms of effective contraception (birth control) for the duration of the study is necessary. Exclusion Criteria: Subject is not in generally good health in the opinion of the investigator Subject has a history of a phototoxic reaction Subject has a history of NB-UVB failure or severe side effects from UVB that resulted in discontinuation of treatment Subject has erythrodermic, pustular, inverse or guttate psoriasis Subject is currently using other psoriasis treatments Subject has used other psoriasis treatments, including herbal products or alternative therapies within 2 months (biologics), 1 month (systemic therapies including methotrexate, cyclosporine and acitretin, PUVA, Broadband UVB, NB-UVB, and tanning beds), or 2 weeks (topical therapies) of first dose of efalizumab or NB-UVB Subject is currently enrolled in any other study except non-treatment, biopsy studies Subject has a history of any form of cancer, including lymphoma, with the exception of non-melanoma skin cancer Subject has a genetic disorder that predisposes to cancer (e.g. xeroderma pigmentosum) Subject has a history of squamous cell cancer within the past 5 years or basal cell cancer within the past 3 months in areas that will be treated with NB-UVB Subject has a history of significant drug or alcohol abuse Pregnant women, nursing mothers, or women planning to become pregnant during the study Subject with congenital or acquired immunodeficiency Subjects planning to have prolonged exposure to the sun or tanning beds during the study which, in the investigator's clinical judgement, may modify the subject's disease severity Subject has a history of lupus erythematosus, bullous pemphigoid or any other photosensitive condition which may worsen with NB-UVB Subject is taking a medication that causes photosensitivity at the discretion of the investigator Subject has an active infection or sepsis prior history or serious infection or tendency to get infections easily Subject has an untreated positive PD Subject has a blood disorder, aplastic anemia, bleeding tendency Subject is allergic to efalizumab or any of its components Subject has any other condition that, in the opinion of the investigator, makes subject a poor candidate for entry into the study Subject will be vaccinated with live vaccines (e.g. Flu-Mist) during the study period.