Assessment of adapalene gel for the treatment of actinic keratoses and lentigines: a randomized trial.

Abstract

Adapalene is a synthetic retinoid with an established clinical efficacy against acne and good local tolerability. Its effectiveness in the treatment of photodamaged skin has not been studied. We sought to determine the safety and efficacy of adapalene gel in the treatment of actinic keratoses and solar lentigines. In a prospective, 2-center, randomized, controlled, investigator-masked, parallel-group study, 90 patients with actinic keratoses and solar lentigines were treated daily with either adapalene gel (0.1% or 0.3%) or its vehicle gel for 4 weeks, followed by twice-daily applications, if tolerated, for up to 9 months. Of the 90 Caucasian patients (69 male, 21 female; mean age 63.1 years) who were enrolled into the study, 83 patients completed 9 months of treatment. With adapalene gel 0.1% and 0.3%, the mean number of actinic keratoses was reduced by 0.5 +/- 0.9 (mean +/- SE) and 2.5 +/- 0.9, respectively. Whereas, with the vehicle gel, there was an increase of 1.5 +/- 1.3 (P <.05). After 1 month of treatment, the patients who received adapalene had significant lightening of solar lentigines as compared with the patients who were treated with vehicle gel (P <.05). After 9 months, 57% and 59% of the patients had lighter lesions in the adapalene 0.1% and 0.3% groups, respectively, in comparison with only 36% in the vehicle group (P <.05). Histologic evaluations revealed improved cellular atypia and reduced epidermal melanin in adapalene-, as compared with vehicle-treated group. The differences, however, were not statistically significant. A retrospective evaluation of paired clinical photographs (before and after 9-month treatment) by 2 dermatologists who were treatment-blinded revealed significant improvement in wrinkles and other clinical features of photoaged skin with adapalene as compared with its vehicle. Adapalene gel 0.1% and 0.3% were well tolerated and improved actinic keratoses, solar lentigines, and other features of photodamaged skin.