Adapalene/Benzoyl Peroxide Gel 0.3%/2.5%: Effective Acne Therapy Regardless of Age or Gender

a highly effective contraceptive method for the duration of the clinical trial; women were excluded from the study if they were using hormonal contraceptives for less than three months prior to the baseline or for any length of time solely for the control of acne. Acceptable contraceptive methods included bilateral tubal ligation, vasectomized partner, combined oral (estrogens and progesterone), or hormonal intrauterine device with a stable dose at least 3 months prior to baseline. To achieve equal distribution of baseline acne severity in the treatment arms, subjects were stratified by IGA score prior to randomization into treatment arms. Randomization was planned with a 3:1 ratio for active:vehicle.

The study treatments were A/BPO gel 0.3%/2.5% or its vehicle. All subjects received a moisturizer and gentle cleanser, along with instructions for product dosing and application (oral and written). Subjects applied the assigned study treatment to the entire face (1 pea-sized amount to the forehead, chin, and each cheek) once in the evening after washing. If the once daily treatment regimen was altered to every other day, the investigator had to attempt to return the subject to once daily treatment within 2 weeks. Subjects were also instructed to apply a thin film to affected areas of the trunk, if applicable. Additionally, subjects were requested to use the moisturizer (up to 3 times daily) and the gentle cleanser throughout the study.

The co-primary endpoints were success rate, defined as the percentage of subjects with an IGA of clear (0) or almost clear (1) and at least a two-grade improvement at week 12, and the change in inflammatory and noninflammatory lesion counts from baseline to week 12.

The incidence of adverse events (AE) was analyzed for all subjects throughout the study. Cutaneous tolerability, measured as erythema, scaling, dryness, and stinging/burning were assessed on a 4-point scale (0–3) at each study visit.

The intent to treat (ITT, all randomized subjects) population was used for efficacy analyses and the safety population (ITT subjects who applied the study drug at least once) was used for cutaneous tolerability and safety analyses. Success rates were analyzed using Cochran-Mantel-Haenszel (CMH) tests and Analysis of Variance with baseline IGA and lesion counts as covariates. The last observation carried forward (LOCF) method was used for success rates and lesion counts.

The following populations are described in Table 1: females and males, and age groups 12 - 17 and ≥ 18 years. There was a similar