A Phase II Study of Photodynamic Therapy (PDT)With LEVULAN® Topical Solution + Blue Light Versus LEVULAN® Topical Solution Vehicle + Blue Light for the Treatment of Actinic Keratoses on the Upper Extremities

Inclusion Criteria:

- At least 4 Grade 1/2 AKs on each upper extremity

Exclusion Criteria:

- Pregnancy

- history of cutaneous photosensitization, porphyria, hypersensitivity to porphyrins or
photodermatosis

- lesions suspicious for skin cancer (skin cancer not ruled out by biopsy) or untreated
skin cancers within the Treatment Area

- skin pathology or condition which could interfere with the evaluation of the test
product or requires the use of interfering topical or systemic therapy

- Subject is immunosuppressed

- unsuccessful outcome from previous ALA-PDT therapy

- currently enrolled in an investigational drug or device study

- has received an investigational drug or been treated with an investigational device
within 30 days prior to the initiation of treatment

- known sensitivity to one or more of the vehicle components (ethyl alcohol, isopropyl
alcohol, laureth 4, polyethylene glycol)

- use of the following topical preparations on the extremities to be treated:

- Keratolytics including urea (greater than 5%), alpha hydroxyacids [e.g.glycolic
acid, lactic acid, etc. greater than 5%], salicylic acid (greater than 2%)
within 2 days of initiation of treatment.

- Cryotherapy within 2 weeks of initiation of treatment

- Retinoids, including tazarotene, adapalene, tretinoin, retinol, within 4 weeks
of initiation of treatment.

- Microdermabrasion, laser ablative treatments, ALA-PDT, chemical peels, 5-FU,
diclofenac, imiquimod or other topical treatments for AK within 8 weeks of
initiation of treatment.

- Two or more ALA PDT treatments in the past 6 months

- use of systemic retinoid therapy within 6 months of initiation of treatment.