A Comparison of 122-0551 Foam Versus Vehicle Foam in Subjects With Plaque Psoriasis (Study 306)

Inclusion Criteria:

• Subject has a clinical diagnosis of stable plaque psoriasis involving a minimum of 2%and no more than 12% affected body surface area.

• Subject has an Investigator's Global Assessment (IGA) score of at least three (moderate) at study start.

• If subject is a woman of childbearing potential, she must have a negative urinepregnancy test and agree to use an effective form of birth control for the duration ofthe study.

Exclusion Criteria:

• Subject has spontaneously improving or rapidly deteriorating plaque psoriasis.

• Subject has guttate, pustular, erythrodermic or other non-plaque forms of psoriasis.

• Subject has a physical condition which, in the investigator's opinion, might impairevaluation of plaque psoriasis, or which exposes the subject to an unacceptable riskby study participation.

• Subject has used any phototherapy (including laser), photo-chemotherapy or other formsof photo based therapy for the treatment of their psoriasis within 30 days prior tostudy start.

• Subject has used any systemic methotrexate, retinoids, systemic corticosteroids [including intralesional, intra-articular, and intramuscular corticosteroids],cyclosporine or analogous products within 90 days prior to study start.

• Subject has used any systemic biologic therapy (i.e., FDA-approved or experimentaltherapy) within five half-lives of the biologic prior to study start.

• Subject had prolonged exposure to natural or artificial sources of ultravioletradiation within 30 days prior to study start or is intending to have such exposureduring the study.