Objective: In the USA, Imiquimod 5% cream is approved for use 2-3 times per week over 16 weeks for the treatment of actinic keratoses (AKs). This study evaluated the efficacy of imiquimod in another treatment schedule, for AKs on the head.
Design: Open-label, phase IIIb.
Setting: 180 dermatology clinics and practices in Germany.
Patients: Patients were eligible if they had clinically typical, visible AK lesions located anywhere on the head, excluding the upper and lower eyelids, nostrils, lip vermilion, and inside the ears.
Interventions: Patients applied study cream to the treatment area once daily 3x/week for 4 weeks (course 1) followed by a 4-week post-treatment period. Patients with AK lesions remaining in the treatment area underwent a second 4-week treatment course.
Main outcome measures: Primary variable was the complete clearance rate, defined as the proportion of patients with no clinically visible AK lesions in the treatment area at the course 1 or course 2 post-treatment visit.
Results: 829 patients entered the study. Overall, the complete clearance rate was 68.9% (571/829) and the partial clearance rate (percentage of patients with >/= 75% reduction in the number of baseline AK lesions) was 80.2%. Local skin reactions (LSRs) and application site reactions (ASRs) were the most commonly reported adverse events. Four patients discontinued from the study due to LSRs or ASRs.
Conclusions: Shorter treatment regimen of imiquimod 5% cream can produce complete clearance rates similar to those seen with 16 weeks of treatment and has the advantage of lower drug exposure, resulting in a better benefit-risk profile for the patient.