Aclaris has announced positive results from its two pivotal Phase 3 trials of A-101 40% Topical Solution (A-101), a novel treatment for seborrheic keratosis (SK).

A total of 937 patients were enrolled in the two identical trials, SEBK-301 and SEBK-302. Patients in both trials had four target SK lesions including at least one on the face and at least one on the trunk or extremities. Overall, 467 patients received A-101 and 470 received placebo.

The validated four-point Physician Lesion Assessment (PLA) rating scale was used to assess outcomes, defining lesions as either clear (PLA=0), near clear (PLA=1), thin (PLA=2), or thick (PLA=3). 

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Results showed that the primary endpoint of clearance (PLA=0) of all four target SK lesions was met by 4% in SEBK-301 and 7.8% in SEBK-302 of those treated with A-101. In SEBK-301 13.5% of patients treated with A-101 achieved clearance of at least three target SK lesions (p<0.0001); while 23% in the SEBK-302 trial achieved clearance of at least three SK lesions (p<0.0001). None of the patients administered placebo achieved clearance of all four target SK lesions in either trial. 

Results also showed that in the combined trials, 51.3% of lesions treated with A-101 were deemed as clear or near clear (PLA1) vs. 7.3% in the placebo group, at trial completion. For face lesions, 65.3% of those treated with A-101 were assessed as clear or near clear at trial completion vs. 10.5% of those treated with the placebo. 

No treatment-related adverse effects were noted among the A-101 treated patients. 

SK lesions affect over 83 million people in the U.S. according to the American Academy of Dermatology and the Society for Investigative Dermatology. “For patients who seek to improve their appearance, a treatment that can achieve clearance or near clearance of lesions while delivering a favorable aesthetic result would represent a significant advance in the standard of SK treatment,” said trial investigator Zoe Draelos, MD, and fellow of the American Academy of Dermatology. 

A-101 (40% topical solution) is a high-concentration hydrogen peroxide formulation being developed for non-invasive, in-office therapy. 

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