Long-Term Effectiveness and Safety of Up to 48 Weeks' Treatment with Topical Adapalene 0.3%/Benzoyl Peroxide 2.5% Gel in the Prevention and Reduction of Atrophic Acne Scars in Moderate and Severe Facial Acne

Abstract

Background: Scarring is a frequent consequence of acne.

Objectives: Our objective was to evaluate the effect of up to 48 weeks' treatment with adapalene 0.3%/benzoyl peroxide 2.5% (A0.3/BPO2.5) gel on atrophic scars in moderate or severe acne vulgaris.

Methods: In Part 1 of this two-part study, A0.3/BPO2.5 gel or vehicle was applied on each half-face for 24 weeks in a randomized, investigator-blinded, split-face design. Part 2 was a 24-week, open-label extension phase during which A0.3/BPO2.5 gel was applied on both sides of the face. Assessments included investigator atrophic acne scar count, Scar Global Assessment (SGA), acne lesion count, local tolerability, and safety.

Results: Of the 45 subjects entering Part 2, 41 completed the 48-week study. At baseline (Part 1), most subjects had moderate acne (93.3%) with mild scars (62.2%). The scar count decrease from baseline was 21.7% at week 24 and 26.9% at week 48 on the half-face treated for 48 weeks with A0.3/BPO2.5. For the half-face treated with vehicle followed by 24 weeks' A0.3/BPO2.5, scar count increased by 16.7% at week 24 (under vehicle) and decreased by 22.7% between weeks 24 and 48. The half-face that received 48 weeks' A0.3/BPO2.5 had a lower final atrophic scar count (mean 8.4 vs. 9.9 for the half-face with 24 weeks' vehicle then 24 weeks' A0.3/BPO2.5) and a higher percentage of SGA clear/almost clear. High reductions in acne lesions between baseline and week 48 were observed for both sides of the face. Long-term treatment with A0.3/BPO2.5 was safe and well-tolerated.

Conclusions: Reductions in atrophic acne scars and acne lesions observed after 24 weeks of treatment with A0.3/BPO2.5 gel were maintained with treatment up to 48 weeks. The additional improvement in atrophic scar count with 48 weeks' A0.3/BPO2.5 treatment, compared to delayed application at 24 weeks, highlights the importance of early initiation of effective acne treatment to prevent and reduce the formation of acne scars.

Trial registration: ClinicalTrials.gov identifier NCT02735421.