An open label, safety study to assess the potential for adrenal suppression following maximal use treatment with DSXS administered twice daily for 28 days in patients with moderate to severe plaque psoriasis.

1. The objective of this study is to evaluate the potential of DSXS to suppress HPA axis function in patients with moderate to severe plaque psoriasis
2. To evaluate the efficacy parameters, pharmacokinetics and adverse event (AE) profile of DSXS

Inclusion Criteria:

1. Patients with a confirmed diagnosis of plaque psoriasis, patients 2-17 years of age with ≥ 10% BSA affected and patients age 18 years of age or older with ≥ 20% BSA affected
2. Investigator Global Assessment (IGA) score of 3 (moderate) or 4 (severe) at baseline for the overall disease severity.
3. Results from a cortisol response test that are considered normal and show no evidence of any abnormal HPA function or adrenal response

Exclusion Criteria:

1. Patients under 2 years of age.
2. Investigator Global Assessment (IGA) of less than 3 (moderate) or greater than 4 (severe) at baseline.
3. Current diagnosis of types of psoriasis other than stable plaque psoriasis (i.e., erythrodermic, exfoliative or pustular psoriasis).
4. Results from a cortisol response test that show evidence of any abnormal HPA function or adrenal response

1 year, 4 months