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.

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.