Study to Assess the Potential for Adrenal Suppression Following Treatment With DSXS in Patients With 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