Cantharidin-based drug-device combination likely safe, effective for molluscum contagiosum

Reuters Health - 03/10/2020 - VP-102, a proprietary drug-device combination containing 0.7% cantharidin, was safe and effective in two phase 3 trials in children with molluscum contagiosum (MC).

Dr. Gary Goldenberg, Chief Medical Officer of study sponsor Verrica Pharmaceuticals in West Chester, Pennsylvania, told Reuters Health by email, "Molluscum contagiosum is one of the most common viral skin infections in children and one of the five most prevalent skin diseases worldwide. Yet, there are no FDA-approved treatments for (it)."

"The positive results from Verrica's Phase 3 CAMP (Cantharidin Application in Molluscum Patients) trials demonstrate that VP-102, which is delivered via a single-use applicator that allows for precise topical dosing and targeted administration, may be a viable treatment option for pediatric and adult patients with molluscum," he said.

"Verrica's next expected milestone for VP-102 is a Type A Meeting with the FDA during September/October," he added.

In two phase-three trials spanning 31 centers across the US, 527 participants (mean age around 7; about half boys) were randomized (3:2) to apply topical VP-102 or vehicle to all treatable lesions every 21 days until complete lesion clearance or up to four treatments.

The main efficacy outcome was the proportion of VP-102-treated participants achieving complete clearance of all MC lesions (baseline and new) compared with those who received vehicle at the end-of-study visit on day 84.

As reported in JAMA Dermatology, treatment with VP-102 was more efficacious than vehicle on day 84 in the percentage of participants with complete clearance of MC lesions for CAMP-1 (46.3% vs. 17.9%) and CAMP-2 (54% vs. 13.4%).

Adverse events occurred in 99% (CAMP-1) and 95% (CAMP-2) of VP-102-treated participants and 73% (CAMP-1) and 66%(CAMP-2) of those who received vehicle. The most common adverse events were application site vesicles, pain, pruritus, erythema, and scab. Most events were mild or moderate.

Adherence was high: 93.2% of participants who received VP-102 and 95.4% of those who received vehicle completed the trials.

The authors conclude, "These trials provide robust efficacy and safety data that support the use of VP-102 for the treatment of MC in participants aged 2 years and older."

Dr. Adam Friedman, Director of Translational Research in the Department of Dermatology at George Washington University in Washington, DC, commented by email, "Cantharadin, or more lovingly called 'beetlejuice,' is an oldie but off-label goodie. We in dermatology have procured it through different avenues for decades to treat viral infections of the skin ranging from MC to the common wart."

"Given the overall ease of securing it, more often from abroad, there was little impetus to seek FDA approval, though its off-label nature and limited access at times has made it difficult, especially in academic centers, to utilize," he told Reuters Health.

"Enter VP-102, taking something that we and our patients are familiar with and often prefer, given the painless nature of application - especially when considering pediatric patients - and offering a new and potentially easier way to deliver it," he said. "I do not foresee that the FDA will hold approval up too long, and hope to have access to this cantharadin 2.0 soon."

Three coauthors are or were employees of Verrica Pharmaceuticals, and most of the rest have received fees from the company.

By Marilynn Larkin

SOURCE: https://bit.ly/3cUcWCG JAMA Dermatology, online September 23, 2020.



Posted on 3 October 202021 October 2020