Conditions: Psoriasis
Keywords: Obese patients (BMI>30) Patients with moderate to severe psoriasis
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 30
Healthy volunteers: yes

Brief summary:
This is a single-center, open-label, pilot study. A total of 30 subjects (15 in each study arm) will be enrolled in this 6 month study to evaluate whether the addition of narrow band UVB (NB-UVB) phototherapy can enhance the efficacy of etanercept's maintenance dose, 50 mg once a week, in obese psoriasis patients.

Detailed description:
In Phase I, all subjects will receive etanercept's induction dose, 50 mg twice a week, for a total of 12 weeks. In Phase II, all subjects will receive etanercept's maintenance dose, 50 mg once a week, during Weeks 12-24. Those subjects randomized to the treatment arm will receive NB-UVB phototherapy 3 times a week during Phase II. In order to ensure homogeneity between the NB-UVB arm and non-NB-UVB arm, subjects will be randomized according to their Body Mass Index (BMI). The Psoriasis Area Severity Index (PASI) score and Physician Global Assessment (PGA) will be calculated at each visit to determine the effectiveness of the etanercept and NB-UVB treatment during both phases of the study. The hypothesis is that the combination of NB-UVB phototherapy three times a week and etanercept maintenance dose (50 mg once a week) will enhance the efficacy of the maintenance dose alone in obese patients (BMI \>30) with moderate to severe psoriasis.

Arms:
arm 1: Subjects will only be treated with etanercept. This is given at the standard FDA approved dosage of 50 mg twice weekly x 3 months then 50 mg once weekly x 3 months. No UVB will be given. Sham UVB will not be used because the subjects are not blinded because they often know they are receiving sham UVB due to differences in light intensity and heat. arm 2: Subjects will receive etanercept. This is given at the standard FDA approved dosage of 50 mg twice weekly x 3 months then 50 mg once weekly x 3 months.

In addition, for months 3-6, subjects will receive Narrow Band Ultraviolet B phototherapy three times a week for 12 weeks in addition to the etanercept maintenance dose. The safety and efficacy of the combination therapy will be evaluated by the registered phototherapy nurses at each phototherapy visit and by the study investigator at monthly visits. NB-UVB therapy will be adjusted according to the clinical judgment of the University of California San Francisco Psoriasis Treatment Center phototherapy staff.

Interventions: intervention 1: Narrow band (310-312 nm) ultraviolet light B phototherapy intervention 2: etanercept
Intervention descriptions: intervention 1: Narrow band (310-312 nm) ultraviolet light B phototherapy 3 times a week during Weeks 12-24. NB-UVB therapy will be adjusted according to the clinical judgment of the University of California San Francisco Psoriasis Treatment Center phototherapy staff intervention 2: Etanercept is given at the standard FDA approved dosage of 50 mg twice weekly x 3 months then 50 mg once weekly x 3 months.

Protocol document: