Safety and efficacy of A-101 hydrogen peroxide topical solution 40% in adults with seborrheic keratosis: results from the Phase III, randomized, double-blind, vehicle-controlled, parallel-group study

Safety and efficacy of A-101 hydrogen peroxide topical solution 40% in adults with seborrheic keratosis: results from the Phase III, randomized, double-blind, vehicle-controlled, parallel-group study

Presenters: Draelos ZD¹, Kempers SE², Smith SR³, Wilson DC⁴; Powala C⁵, Bradshaw M⁶; Estes E⁵; Shanler S⁵

Affiliations: ¹Dermatology Consulting Services, High Point, NC; ²Minnesota Clinical Study Center, Fridley, MN; ³California Dermatology & Clinical Research Institute, Encinitas, CA; ⁴The Education and Research Foundation, Inc., Lynchburg, VA; ⁵Aclaris Therapeutics, Malvern, PA

Objective: Seborrheic keratosis (SK) is one of the most common benign skin lesions, affecting over 80 million Americans, yet there is no United States Food and Drug Administration (FDA)-approved treatment available. The purpose of this study was to evaluate the safety and efficacy of a proprietary 40% hydrogen peroxide topical solution (A-101) versus its matching vehicle for the treatment of seborrheic keratosis.

Design: Adults with four eligible SK lesions identified by the study investigator were randomized 1:1 to A-101 or a matching A-101 vehicle. Eligible lesions were stable, typical SKs, measuring 5 to 15mm in both width and length and less than 2mm in thickness. Subjects were required to present with at least one lesion on the trunk or extremities and at least one lesion on the face. All treatments were performed by a non- physician sub-investigator to maintain blinding. All lesions were treated on Day 1. Previously treated SK lesions with a Physician’s Lesion Assessment score over 0 were re-treated on Day 22 (PLA scale: 0=clear, 1=near clear, 2=thickness ?1mm, and 3=thickness>1mm). At Day 106, the investigator assessed the lesions using the validated PLA scale.

Results: Total of 450 subjects were enrolled. At Day 106, significantly more subjects receiving A-101 (intent-to-treat ITT population) completely cleared (PLA=0) all four lesions (4% vs. 0%, P<0 .002) and 3 of 4 lesions (13.5% vs. 0%, P<0.0001) versus vehicle in the primary and secondary endpoints, respectively. In the a priori exploratory analyses (per protocol population [PPP], n=439), significantly higher mean per-subject percentage of lesions achieving clear or near clear (PLA?1) was observed in the A-101 arm (47.5% vs. 10.2%; P<0.0001). Significantly higher mean per-subject percentage of facial lesions achieving clear or near clear (PLA?1) was also observed (64.4% vs.15.0% at Day 106; P<.0001). Adverse events were comparable between groups.

Local skin reactions were predominantly mild and generally resolved by Day 106. At all visits, atrophy, erosion, hypopigmentation, scarring, or ulceration were reported for at least four percent of lesions.

Conclusion: A-101, a 40% hydrogen peroxide topical solution, is a safe, effective, and well-tolerated treatment for SK. If approved, it would offer the first FDA-approved topical treatment for SK.