Treatment of Actinic Keratoses of the Face With Imiquimod 3.75% Cream Followed by Photodynamic Therapy

Actinic keratoses are common skin lesions associated with solar ultraviolet radiation
exposure. Some actinic keratoses may develop into skin cancers.

Imiquimod 3.75% cream is an approved treatment for actinic keratoses that utilizes a regimen
of application to the entire face or balding scalp of up to 2 packets of cream daily for two
2-week cycles, separated by a 2-week no treatment interval.

Photodynamic therapy with aminolevulinic acid (ALA) 20% topical solution is also an approved
treatment for actinic keratosss. ALA is applied to actinic keratoses, and after an
incubation period, is excited with light. Although approved as a lesion-directed treatment
for actinic keratoses, treatment of a field (e.g. face) with photodynamic therapy is
commonly performed.

Treatment with photodynamic therapy followed by imiquimod 5% cream has been reported in
patients with actinic keratoses, basal cell carcinoma and Bowen's disease, and treatment
with imiquimod 5% cream followed by photodynamic therapy in patients with vulvar
intraepithelial neoplasia. There are, however, no prior studies on the safety and/or
efficacy of using topical imiquimod 3.75% in conjunction with photodynamic therapy in the
treatment of actinic keratoses.

This study will use an open-label parallel cohort design in which all patients will received
treatment with imiquimod 3.75% cream, and subsequently will be will be randomized to either
photodynamic therapy or observation.

Inclusion Criteria:

- Male and female adults; 18 and over

- At least 10 and no more than 30 clinically typical actinic keratoses on the face

Exclusion Criteria:

- Hypertrophic actinic keratoses or other skin lesions on the head that might required
excluded treatment during the study

- Known contraindication to treatment with imiquimod or photodynamic therapy

- Condition that would limit compliance, be a potential safety risk, or require therapy
with an excluded treatment

- Systemically immunocompromised

- Pregnant or nursing

- Dermatologic disease and/or condition in treatment area that might exacerbated by
treatment with imiquimod, cause difficulty with examination, or require therapy with
an excluded treatment

- Participation in another clinical study

- Treatment within the past 60 days with:

- Ultraviolet therapy

- Systemic immunomodulators

- Chemotherapeutic or cytotoxic agents

- Investigational agents

- Treatment on the head within the past 60 days with:

- Imiquimod

- Photodynamic therapy

- Red or blue light source therapy

- Cryotherapy or chemotherapy

- Surgical excision or curettage

- Topical corticosteroids

- Laser

- Dermabrasion

- Chemical peel

- Topical retinoids

- Topical 5-fluorouracil

- Topical pimecrolimus or tacrolimus

- Topical diclofenac

- Treatment for actinic keratoses on the head within the past 60 days