Light Treatment Effectiveness (LITE) Study

Inclusion Criteria:

Willing and able to provide informed consent (age 18+) or parental permission and assent (ages 12-17)
Age 12 or older
Plaque or guttate psoriasis predominantly located on trunk and/or extremities, with a physician global assessment average of >1.0, and considered a candidate for phototherapy

Patient is deemed willing and able to comply with either in-office or in-home phototherapy:

In office: Able to travel about 3 times per week for 12 weeks from home, work and/or school during business hours of local site
In home: Has space to accommodate home phototherapy unit and patient (or if 12-17, parent), willing and able to follow home phototherapy instructions
New or established patient in the practice

Exclusion Criteria:

Patients who are judged unable or unwilling to comply with either in office or in home phototherapy due to time, work, school, or other financial constraints

Patients judged unable to follow home phototherapy protocol due to failure to demonstrate understanding of the following:

How to operate the phototherapy device
How to follow the dosing protocol
Requirement to wear protective eyewear and genital protection equipment
Patients with known history of lack of efficacy to phototherapy or treated with phototherapy 14 days prior to baseline visit
Psoriasis predominantly located on scalp, body folds, genitals, palms and/or soles or with a physician global assessment average of ≤ 1.0

Patients deemed unsafe to be treated with phototherapy:

History of photosensitivity or autoimmune disease such as lupus or dermatomyositis which can be aggravated by ultraviolet radiation
History of arsenic intake
Unable to tolerate standing for required duration of treatment due to age or physical function
History of melanoma or multiple non-melanoma skin cancers that in the opinion of the principal investigator contraindicates treatment with phototherapy
Clinical site deems the participant is ineligible for reason other than eligibility or screening criteria.