Verrica's Phase III Success Paves Way For Filing Of New Cantharidin Formulation VP-102

After reporting positive pivotal data for VP-102 in the contagious skin disease molluscum, Verrica is looking forward to a 2020 launch, with plans to price for broad access.

Verrica Pharmaceuticals Inc.'s success in two Phase III studies – CAMP-1 and CAMP-2 – of its cantharidin formulation VP-102 for the skin disease molluscum puts the product on track for a US FDA filing in the second half and a potential launch in 2020.

Currently, nothing is FDA-approved for molluscum contagiousum, a disease caused by a pox virus that affects about six million people in the US, mainly kids aged two to 14 years. Symptoms include skin lesions that last up to two years. The condition usually clears on its own, but is highly contagious and troublesome — some patients have over 100 lesions.

Treatment options include cryotherapy and curettage, but these are painful and difficult for children to tolerate.

Since the 1950s, topical cantharidin has been accepted as a gold standard treatment by dermatologists, CEO Ted White explained in an interview with Scrip, but it was never officially approved by the FDA. Consequently, it is made in only a handful of compounding pharmacies in in the US and is difficult to obtain – some physicians import it illegally from Canada. (Also see "New FDA panel to review substances for compounding" - Scrip, 26 Jan, 2015.)

Verrica's VP-102 is a drug/device combination that includes a 0.7% solution of cantharidin.

White said that the company has improved on the delivery of cantharidin in terms of convenience and stability. The product comes in a glass vial and is given with an applicator that allows precise dosing.

Verrica's product also includes a purple coloring agent. For patients with many lesions, this is helpful in providing a "visual tracker where a provider can see which lesions have been treated," White said.

The formulation also has an agent that makes the therapy taste bitter in order to deter children from licking it.

Phase III Data In Line With Prior Reports

On Jan. 3, Verrica announced positive top-line results from CAMP-1 and CAMP-2, both of which compared VP-102 to placebo and involved a total of 528 participants.

The drug was given once every 21 days for up to four applications. The primary endpoint was the proportion who got complete clearance of all treatable molluscum lesions after 84 days and secondary endpoints included complete clearance after 21, 42 and 63 days.

For those treated with VP-102, the percent getting complete clearance of all treatable lesions at day 84 was 46% and 54% for CAMP-1 and CAMP-2, respectively. That compares with 18% and 13% for placebo in these studies, a statistically significant difference (p<0.0001).

The mean reductions in lesions at day 84 – a secondary endpoint – were 69% and 83% at day 84 for those on VP-102 in CAMP-1 and CAMP-2, respectively. That compares with 20% and 19% for placebo.

The drug also demonstrated significantly better results for secondary endpoints related to complete clearance after 63 days and 42 days and 21 days in CAMP-1 and significantly better complete clearance after 63 days and 42 days in CAMP-2.

Furthermore, the company noted that the side effect profile was attractive, with mostly mild-to-moderate adverse events and no treatment-related serious adverse events reported for those on VP-102 in either of the pivotal studies.

The most common adverse event reported was application site vesicles, reported in 81% on VP-102 vs. 25% in CAMP-1 and 94% vs. 30% for placebo in CAMP-2. The next most common adverse events reported were pain, pruritis, erythema, discoloration and dryness – all at the application site.

The dropout rates were low, at 3% in CAMP-1 and less than 1% in CAMP-2.

Results are largely comparable to the previously reported INNOVATE study of VP-102, a study of 32 patients where the drug demonstrated a 50% clearance rate and a 98% mean reduction in molluscum lesions, Jefferies analyst David Steinberg said in a Jan. 3 note, concluding that the drug is "eminently approvable."

"With this positive data set in hand, VP-102 looks to become the first FDA-approved drug for molluscum," Steinberg said.

"Of note, VP-102 patients began to demonstrate statistically significant separation from placebo by the third week of the CAMP-1 study whereas statistically significant separation was achieved by the sixth week in the CAMP-2 trial. [Management] indicated that the [Phase III] trials were completed [about] two months ahead of schedule – suggesting very high unmet need for an approved molluscum treatment," Steinberg said.

The product is given every three weeks for a maximum of 12 weeks and must be administered by a clinician. The company has not determined a price yet but notes that research suggests that pricing at $500 to $600 per treatment starts to attract more negative attention and restrictions from payers. A price of $250 or $300 per applicator would equate to a per patient amount of at least $1,000 with a large addressable market.

"We clearly understand the value of low net cost and want to make sure this product is available to all patients," White told Scrip.

Verrica will be doing more market research with payers to inform its pricing strategy for the product.

About 6m have the disease in the US but only about one-fifth of these are actually diagnosed. The condition suffers from "benign neglect," due the lack of treatment options physicians often take a wait-and-see approach, White explained.

Other drugs in development for molluscum include Novan Inc./Sato Pharmaceutical Co. Ltd.'s SB206 topical nitric oxide topical treatment, which just completed Phase II.

Planning To Launch

Verrica envisages launching in early 2020 and expects that it will need 50 sales reps to call on office-based dermatologists in the community and the small number of specialist pediatric dermatologists in teaching institutions.

The company raised $87m in June and had $97m in cash at the end of the third quarter, enough to keep going for two years.

Verrica's VP-102 is also in Phase II for an indication in common warts, which affect some 22m patients in the US, and data is expected in the second quarter.

"While there are some [over-the-counter] agents available (i.e., salicylic acid preparations), they are slow acting and often do not work well. Moreover, cryotherapy is also utilized to treat common warts but the procedures can be painful (e.g., not well suited for children) and occasionally can lead to scarring and dyspigmentation. Hence, given 22M people in the US are afflicted with this condition with at least 2M seeking treatment annually, we believe there is a significant opportunity for an effective Rx product," Jefferies' Steinberg said.

Verrica sees itself focusing on dermatology in areas of high unmet need, potentially including orphan indications. Its VP-102 will be evaluated for the treatment of genital warts in a Phase II trial starting in the second half and a higher dose formulation of cantharidin – VP-103 – is being tested for plantar warts.

Verrica's stock closed up by 6.9% at $8.50 on Jan. 3.