Graceway has provided the results from a phase III program evaluating short-course regimens of two concentrations of imiquimod cream (3.75% and 2.5%). The data demonstrated imiquimod 3.75%, administered daily on two two-week treatment cycles, separated by a two-week non-treatment period, produced clearance rates superior to placebo for actinic keratosis (AK).
The company also reported that FDA has accepted new drug application (NDA) for review of imiquimod 3.75%, utilizing a two-week cycle regimen in the treatment of AK.
Imiquimod 3.75% was also more effective than 2.5% with comparable safety. The existing approved 5% imiquimod formulation is indicated only for the treatment of nonhyperkeratotic, nonhypertrophic AK on a very limited area of the skin, for a full 16 weeks of treatment.
Study demonstrated that total AK lesions were reduced with imiquimod by 82% (imiquimod 3.75%) and 72% (imiquimod 2.5%). The data revealed that patients treated with 3.75% cream and 2.5% cream imiquimod showed greater rates of complete clearance of AKs – 36% and 31%, respectively, as compared to 6% for patients treated with placebo.
Moreover, imiquimod treatment also resulted in higher partial clearance rates, defined as less than 75% reduction in AK count, in 59% (imiquimod 3.75%), and 48% (imiquimod 2.5%) of patients, versus only 23% of placebo treated patients.
Neil Swanson, professor and chairman of Department of Dermatology, Oregon Health and Science University, said: “Topical imiquimod 5% can be difficult for some AK patients because of the required full 16-week dosing. These data demonstrate the two-week cycle regimen at a lower concentration may be an effective and convenient treatment option.”