Aclaris Therapeutics, Inc., shared positive results from its Phase 3 clinical trial, THWART-2 (WART-302), of A-101 45% Topical Solution, an investigational new drug for the treatment of common warts (verruca vulgaris). A-101 45% Topical Solution met the primary and all secondary efficacy endpoints, achieving clinically and statistically significant clearance of common warts. A-101 45% Topical Solution is a proprietary high-concentration hydrogen peroxide topical solution being developed as a potential prescription treatment for common warts. 

THWART-2 is one of two randomized double-blind vehicle-controlled Phase 3 pivotal trials conducted by Aclaris to evaluate A-101 45% Topical Solution as a potential treatment for common warts. Aclaris expects to report data from THWART-1 (WART-301), the second Phase 3 trial during the fourth quarter of 2019. Both trials evaluated the efficacy and safety of A-101 45% Topical Solution as compared to placebo (vehicle). The two randomized, double-blind, vehicle-controlled trials were designed to demonstrate the efficacy and safety of A-101 45% Topical Solution for the potential treatment of common warts when applied by subjects (or the parents/guardians of subjects < 18 years).

In the THWART-2 trial, 502 subjects who had one to six warts at baseline were randomized and self-administered either A-101 45% Topical Solution or vehicle twice a week over 8 weeks, for a total of 16 treatments. The trial achieved its primary endpoint with a high degree of statistical significance (p<0.0001), i.e. a higher proportion of subjects treated in the A-101 45% Topical Solution arm versus vehicle had all their identified common warts reported as clear at Day 60. Warts were assessed using the Physician Wart Assessment scale (PWA=0) which is a validated four-point scale of the investigators’ assessment of the severity of all treated warts. 

In the trial, all secondary efficacy endpoints achieved statistical significance in favor of A-101 45% Topical Solution versus vehicle and are described as follows:

• Complete clearance of all warts at Day 137 (12 weeks after last treatment) (p=0.0001)
• Mean per subject percent of treated warts cleared at Day 137 (p<0.0001)
• Clearance in subjects with a single baseline wart at Day 60 (p=0.0006)
• Time to complete clearance of all warts (p<0.0001)

There were no treatment-related serious adverse events (SAEs) in subjects treated with A-101 45% Topical Solution; however, SAEs of intestinal obstruction (in the A-101 45% Topical Solution group) and staghorn renal calculus (vehicle group) were assessed by the investigators as unrelated. Treatment-related application site adverse events (AEs) were reported in 53.4% and 8.4% of the A-101 45% Topical Solution and vehicle groups respectively. In the active arm 2% (5 subjects) of application site events were severe (1 pain, and 4 site pallor). The most common AEs (occurring in more than 5% of subjects) were application site pain, pallor, erythema, pruritus, scabbing and erosion. No subjects withdrew because of AEs. 

“There are no FDA approved prescription treatments for common warts and we are excited by these data and look forward to the results of the second pivotal Phase 3 trial, THWART-1 (WART-301),” said Dr. Neal Walker, President and CEO of Aclaris. “This treatment is self-administered twice a week for 8 weeks (a total of 16 applications) and we believe these results will be of interest to partners seeking to commercialize A-101 45% Topical Solution.”