Pharmacokinetics of 122-0551 and Its Effects on Adrenal Suppression

Inclusion Criteria: * Subject has a clinical diagnosis of stable plaque psoriasis 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 used any phototherapy, photo-chemotherapy or systemic psoriasis therapy within 30 days prior to initiation of treatment * Subject has used systemic corticosteroids or topical, inhaled, intranasal corticosteroids within 30 days and 14 days, respectively, prior to study screening * Subject has had prolonged exposure to natural or artificial sources of ultraviolet radiation within 30 days prior to initiation of treatment * Subject has used topical psoriatic therapy including tar, anthralin, retinoids, vitamin D analogs (e.g., Dovonex®) within 14 days prior to initiation of treatment * Subject has used emollients/moisturizers on areas to be treated within one day prior to initiation of treatment * Subject is currently using lithium or Plaquenil (hydroxychloroquine) * Subject is currently using a beta-blocking medication (e.g., propranolol) or angiotensin converting enzyme (ACE) inhibitors (e.g., lisinopril) at a dose that has not been stabilized * Subject is pregnant, nursing or planning a pregnancy during the study period * Subject is currently enrolled in an investigational drug, biologic or device study * Subject has received an investigational drug, biologic or an investigational device within 30 days prior to study start * Subject has been previously enrolled in this study and treated with the test article * Subject has an irregular sleep schedule or works night shifts