The objective of this study is to evaluate the potential of desoximetasone 0.25% topical spray to suppress HPA axis function. The potential for adrenal suppression will be assessed following multiple dosing with Desoximetasone 0.25% Topical Spray in patients with moderate to severe plaque psoriasis. The secondary objectives are to evaluate the efficacy parameters and to evaluate the adverse event (AE) profile.

Inclusion Criteria:

• Have a definite clinical diagnosis of stable plaque psoriasis with the extent of BSA affected as designated for each group
• Group 1: involvement of 10-15% of their BSA
• Group 2: involvement of > 15% of their BSA
• Have a Physicians Global Assessment (PGA) score of 3 (moderate) or 4 (severe) at baseline for the overall disease severity.
• Results from a cortisol response test that are considered normal and show no evidence of any abnormal HPA function or adrenal response. Patients must fulfill all of these stipulations:

Exclusion Criteria:

• Female who is pregnant, nursing, planning to become pregnant during the duration of the study, or if of child bearing potential and sexually active not prepared to use appropriate contraceptive methods to avoid pregnancy.
• Patient has current diagnosis of types of psoriasis other than stable plaque psoriasis (i.e. acute, guttate, erythrodermic, exfoliative or pustular psoriasis) or has psoriasis of any kind on the face or scalp that will require active treatment during the study.
• Patient has a history of psoriasis that has been unresponsive to topical corticosteroid therapy.
• In the Investigator's opinion, the patient has other dermatological conditions, such as atopic or contact dermatitis, that may interfere with the clinical assessments of the signs and symptoms of psoriasis
• Patient has a history of allergy or sensitivity to corticosteroids or history of any drug hypersensitivity or intolerance which, in the opinion of the Investigator, would compromise the safety of the patient or the results of the study.
• Patient has a history of an adverse reaction to CortrosynTM or similar test reagents.
• Patient has a significant history or current evidence of chronic infectious disease, system disorder, organ disorder or other medical condition that in the Investigator's opinion would place the study patient at undue risk by participation in the study.
• Patient is currently receiving or has received any radiation therapy, anti-neoplastic agents or immunosuppressant medication within 4 weeks prior to the first dose of study drug.
• Patient has undergone treatment with any systemic or photo antipsoriatic therapy within 8 weeks of the first dose of study drug.
• Patient has been treated within 12 weeks (or five half lives whichever is less) prior to the first dose of study drug with any biological therapies for psoriasis.
• Patient has received any systemic steroids within 4 weeks of the first dose of the study drug.
• Patients who have used any topical antipsoriatic agents of any kind or any topical corticosteroids for any reason within 2 weeks prior to first use of study drug

4 months