Excimer Laser Phototherapy Outcomes in the Treatment of Psoriasis

Study Overview
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Brief Summary
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The purpose of this study is to determine the best dosing strategy when using Excimer Laser to treat plaque-type psoriasis. In this study, half of the body's psoriasis will be treated with a new dosing strategy, and the other half will be treated with the conventional method. We hope to show that the new dosing strategy will result in faster improvement of psoriasis.

Detailed Description
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This is a randomized, assessor-blinded clinical trial to determine whether a novel plaque-based dosimetry strategy can improve the speed of response to excimer laser treatment in patients with plaque psoriasis. Each patient will receive plaque-based dosing on one side of the body and conventional dosing on the contralateral side. This design is based on the assumption that psoriasis usually affects patients in a symmetric distribution (e.g., knees and elbows) and the effect of excimer laser phototherapy is limited to the treated plaque. The side of the body treated with plaque-based dosimetry will be assigned using a table of random numbers. The assessor will be blinded to the treatment group. Each patient will be treated 1-2 times per week at the discretion of the investigator for a maximum of 10 treatments.

Official Title
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A Randomized Clinical Trial to Determine Whether a Novel Plaque-based Dosimetry Strategy Can Improve the Speed of Response to Treatment in Patients With Plaque Psoriasis (Photos)

Conditions
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Psoriasis

Intervention / Treatment
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* Device: Excimer laser phototherapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of chronic plaque psoriasis for at least 6 months Age ≥ 18 years Body surface area affected ≤ 10 percent Presence of at least one pair of bilateral target lesions with an area of at least 20 cm2 per target lesion. The bilateral target lesions must be present in the same category of anatomical region (e.g., bilateral lower extremities, bilateral upper extremities or bilateral trunk). Exclusion Criteria: active or past history of erythrodermic psoriasis, guttate psoriasis, or pustular psoriasis history of photosensitivity disorder history of malignant melanoma active, invasive non-melanoma skin carcinoma Fitzpatrick Skin Type I Subject has received ultraviolet B phototherapy or any topical anti-psoriatic therapy within two weeks prior to starting the study. Subject has received systemic or topical psoralen-ultraviolet A photochemotherapy within four weeks prior to starting the study. Subject has received biologic therapy within three months of starting the study.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Conventional Dosing<br>Patients psoriasis to be treated with Excimer laser phototherapy based on conventional dosing guidelines. These guidelines determine the starting dose based on plaque thickness and the skin type of the patient. Patients will also be evaluated for psoriasis plaque response to test doses. The best dose will be selected from a test matrix of doses. | Device: Excimer laser phototherapy<br>* Excimer laser phototherapy is a type of ultraviolet light that is applied to psoriatic plaques. It is administered using a laser in a targeted way so that only the plaques are treated (normal skin is not treated).<br>|
| Experimental: Plaque based dosing<br>Patients will also be evaluated for psoriasis plaque response to test doses. The best dose will be selected from a test matrix of doses. | Device: Excimer laser phototherapy<br>* Excimer laser phototherapy is a type of ultraviolet light that is applied to psoriatic plaques. It is administered using a laser in a targeted way so that only the plaques are treated (normal skin is not treated).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Modified Psoriasis Area Severity Index | The Modified Psoriasis Area Severity Index is a scale that grades psoriasis based on thickness, redness, scaling, and area involvement. | 10 weeks |