Potential Effect of Topical Imiquimod on Atrial Ectopy in Patients With Actinic Keratosis

This study is a double-blind, randomized, placebo-controlled, 2-way crossover study designed
to assess the potential effect of topically applied 3.75% imiquimod cream on atrial ectopy
in actinic keratosis (AK) patients. Candidates for study participation will begin screening
procedures up to 28 days prior to enrollment. Qualified subjects shall be admitted to the
CRU on Day -1 for baseline evaluations and will be randomized to one of two possible
treatment sequences. Each subject will receive both the active 3.75% imiquimod cream and the
matching placebo in a randomized crossover fashion with a 2-week washout in between each
treatment. The application area is the entire face (exclusive of nares, vermilion,
periocular areas and ears) or balding scalp. Atrial ectopy will be monitored for 24 hours at
Baseline (Day -1; prior to the first dose of study medication), and at the conclusion of
each 14-day treatment period using a continuous 12-lead digital Holter recorder.

Adverse events, concomitant medication use, study medication accountability, and subject
compliance will be reviewed at each visit.

Inclusion Criteria:

- Male and female AK patients with at least 5 typical visible or palpable AK lesions on
face or balding scalp

- AK patients in otherwise good general health age 18 years and above

- Female subjects of childbearing potential must be non-pregnant and non-lactating

Exclusion Criteria:

- Previous clinical study participation within 30 days (drug or device)

- Evidence of clinically significant diseases

- History of drug or alcohol abuse

- Subjects with uncontrolled systemic hypertension, NYHA heart failure classification
Class > II, or a history of atrial fibrillation or atrial flutter

- Subjects using imiquimod or interferon within 30 days prior to the first dose of
study medication

- Have known allergies to any excipient in the study cream

- Have melanoma anywhere on the body