Objective: To assess the efficacy and safety of a topical gel containing clindamycin 1.2% and tretinoin 0.025% for the treatment of acne and acne-induced postinflammatory hyperpigmentation (PIH) in darker skinned patients.
Design: Randomized, double-blind, placebo-controlled study.
Setting: Two United States clinical sites.
Participants: Thirty-three patients 12 years of age or older with skin types IV to VI, mild-to-moderate facial acne, and PIH were enrolled.
Measurements: Patients applied clindamycin phosphate/tretinoin gel or a nonmedicated vehicle each evening and a sun protection factor 30 sunscreen daily. Changes in skin erythema and hyperpigmentation were measured using a chromameter and photographic images. Efficacy was assessed using the Evaluators Global Acne Severity Scale, lesion counts, Post-inflammatory Hyperpigmentation Severity Scales and Patient's Global Assessment Scale. Safety and tolerability were assessed by adverse event reports and a Safety Assessment Scale.
Results: The mean (SD) baseline inflammatory lesion count was 11.9 (11.1) in clindamycin/tretinoin-treated patients, decreasing by 5.5 (6.56) after 12 weeks while the mean baseline inflammatory lesion count was 13.6 (11.15) in placebo-treated patients, decreasing by 4.1 (11.36) (p=0.05 for change from baseline, clindamycin/tretinoin vs. placebo). Clindamycin/tretinoin-treated patients generally demonstrated superior efficacy versus placebo treatment. The clindamycin/tretinoin topical gel was well tolerated, causing little or no irritation, although one patient withdrew due to periorbital edema of moderate severity possibly related to clindamycin/tretinoin gel.
Conclusion: Although limited by small sample size, the results of this pilot study suggest clindamycin phosphate 1.2% and tretinoin 0.025% topical gel is a safe and effective option for treating mild-to-moderate acne in patients with skin of color.