Evaluate Safety and Tolerability of Calcipotriene Foam 0.005% in Pediatric Subjects With Mild/Moderate Plaque Psoriasis

This is a multicenter, open-label, Phase 1 study in a total of 75 pediatric subjects, ages 2 to 11 years, inclusive, with mild or moderate plaque psoriasis. The study will enroll sufficient subjects with plaque psoriasis and an ISGA score of mild to moderate (score of 2 or 3) at Baseline to ensure 50 evaluable subjects in a general use cohort. In addition, a sufficient number of subjects with moderate plaque psoriasis will be enrolled to ensure 25 evaluable subjects in a 'maximum-use' cohort that have: A. At least 10% total BSA with some scalp involvement (15 evaluable subjects ages 7 to 11 years) or B. At least 3% total BSA with some scalp involvement (10 evaluable subjects ages 2 to 6 years). "Napkin" psoriasis (psoriasis in the diaper area) can be included in the BSA calculation for this age group. Subjects or their caregivers will apply a thin layer of study product twice a day to the treatment areas for 8 weeks. Any new psoriatic lesions appearing in treatment areas during the treatment period should also be treated with study product. Safety assessments (adverse event and serious adverse event query) will occur at all study visits. Treatment effect assessments, urine calcium metabolism assessments, and application site tolerability assessments will be performed for all subjects at all in-clinic visits. A blood sample will be taken from all subjects at Screening for evaluation of pharmacodynamic (PD) and 2,5-OH vitamin D levels, an additional blood draw for PD parameters will be taken at Week 2 for the maximum-use cohort only. Blood sampling for pharmacokinetic (PK) measurements will be performed in the maximum-use cohort at Screening and Week 2.