NEW YORK (Reuters Health) - A type of skin lesion called actinic keratosis, caused by long-term exposure to the sun, responds well to prescription Aldara cream applied three times a week in one or two month-long courses, a study shows. The cream contains a 5 percent concentration of the drug imiquimod.
In the study, reported in the Journal of the America Academy of Dermatology, this treatment successfully cleared all skin lesions in more than half of cases.
Actinic keratoses consist of abnormal skin cells, probably resulting from immune suppression caused by ultraviolet light, and they can sometimes become cancerous. Imiquimod stimulates the body's own immune system to fight various conditions.
Dr. Joseph Jorizzo, at Wake Forest University School of Medicine in Winston-Salem, North Carolina, and associates designed their study to confirm preliminary findings that shorter courses of imiquimod may be as effective as the 16-week course approved by the US Food and Drug Administration.
"Most patients are not willing to undergo a 16-week course of treatment," Jorizzo told Reuters Health. "Aldara has a lot of flexibility, so in the practical clinical setting, patients can use it exactly as we did in the paper, or they can compress the treatment even more."
Patients with four to eight visible actinic keratoses located on the balding scalp or face were randomly assigned to treatment with imiquimod cream or to inactive sham-cream (the controls) applied three times per week for 4 weeks. There were 123 patients in each group.
Jorizzo and his colleagues report that, at a 4-week posttreatment evaluation, all skin lesions within the treatment area were cleared in 32 patients in the imiquimod arm but only 5 in the control arm.
Those with remaining lesions underwent a second 4-week course of treatment. Eighty-six patients in the imiquimod arm completed the second course, as did 113 in the control group. Among these subgroups, skin lesions cleared in 33 and 13 patients, respectively, at the second post-treatment check.
