Summary

The current treatment of acne includes topical retinoids, which promote fibroblasts to produce more procollagen. Therefore, it is feasible that topical retinoids may improve preexisting atrophic acne scars or be used for scar prevention. This article discusses a study looking at whether adapalene-BPO treatment could prevent acne scarring and to determine the relationship between primary and secondary acne lesions.

  • Dermatology Clinical Trials
  • Skin Diseases
  • Dermatology
  • Dermatology Clinical Trials
  • Skin Diseases

Adapalene-benzoyl peroxide (BPO) fixed-dose combination resulted in a decrease in the number of lesions and new scars but had no effect on preexisting scars in patients with moderate acne vulgaris over 24 weeks. Philippe Martel, MD, Galderma Research and Development, Sophia Antipolis, France, presented data from a study that evaluated the effect of fixed-dose adapalene-BPO for the prevention and treatment of atrophic acne scars.

The current treatment of acne includes topical retinoids, which promote fibroblasts to produce more procollagen. Therefore, it is feasible that topical retinoids may improve preexisting atrophic acne scars or be used for scar prevention. The purpose of this study was to determine if adapalene-BPO treatment could prevent acne scarring and to determine the relationship between primary and secondary acne lesions.

In this international, multicenter, investigator-blinded study, 38 patients with moderate acne vulgaris were randomly assigned in a split-face fashion to receive adapalene-BPO or placebo gel 5 to 7 days per week for 24 weeks. A total of 31 patients completed the study. Moderate acne was defined as 20 to 40 inflammatory lesions (except the nose), ≥ 10 atrophic acne scars (except the nose), and ≤ 1 acne nodule. Treatment compliance was measured by an at-home video camera via the Clinical Compliance Control System, which also guided patients during drug application to avoid errors. The mean compliance rate was 77.4%. In addition, patients recorded application of the study treatment in a diary, which was reviewed by the study dispenser at each follow-up visit. End points were the lesion count at 24 weeks, inflammatory and noninflammatory lesion count, the number of scars, the Scar Global Assessment (SGA) of the clearance of scars, and scar volume.

The mean total lesion count was lower with adapalene-BPO compared with placebo (16.1 vs 8.5; P < .001). The number of inflammatory and noninflammatory lesions was significantly reduced from baseline with adapalene-BPO compared with placebo (change of 4 and 3.6 lesions, respectively; P < .001 for both).

The mean number of scars ≥ 2 mm using a clinical grading scale decreased by 1.96 at 24 weeks in the adapalene-BPO group compared with the placebo group. In addition, the area that was clear and almost clear of scars as measured by the SGA increased from baseline with adapalene-BPO treatment compared with placebo at week 24, whereas the proportion of skin with mild scars decreased in the adapalene-BPO-treated skin. The proportion of skin that had moderate scarring decreased at similar levels from baseline in both groups; however, the proportion with severe scarring remained the same. Scar volume, as measured by a 3-dimensional analysis, did not change over the study period of 24 weeks, suggesting that treatment with adapalene-BPO does not affect preexisting scars.

During the study, scars formed continuously, with 36% resolved by 24 weeks (mean duration of 41 days) and 64% remaining. Papules and postinflammatory lesions resulted in 98% of scars, and the probability of scar occurrence from inflammatory lesions was 5.7%.

In conclusion, Prof Martel stated that treatment with adapalene-BPO fixed-dose combination compared with placebo was superior for the treatment of acne scars, with a reduction of 1.96 in the number of scars ≥ 2 mm at 24 weeks. The number of scars continued to increase with placebo, whereas the number was stabilized with treatment. The duration of the papules appeared to be the main contributor to the risk of scarring.

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