UC San Diego

Background

Compounded cantharidin has been used for decades to treat molluscum contagiosum but lacks rigorous clinical evidence to support its safety and efficacy. VP-102 is a shelf-stable drug-device combination product that contains topical cantharidin (0.7% weight/volume [w/v]) and is being evaluated for the treatment of molluscum.

Objectives

Our objective was to present pooled safety and efficacy analyses of VP-102 in the treatment of molluscum compared with vehicle.

Methods

Participants aged ≥ 2 years were randomized 3:2 to topical administration of VP-102 or vehicle in two randomized, double-blind, vehicle-controlled phase III trials. Study drug was applied to all baseline and new lesions once every 21 days until clear or for a maximum of four applications. Assessors blinded to treatment counted all lesions at each study visit. All adverse events (AEs) were documented. Data were pooled for analyses.

Results

In total, 310 participants received VP-102 and 218 received vehicle. Mean age was 7.5 years (range 2-60) for VP-102 and 6.8 (2-54) for vehicle. Complete clearance of all molluscum lesions at day 84 occurred in 50% of VP-102 participants and 15.6% of vehicle recipients (p < 0.0001). Mean molluscum lesion counts decreased 76% for VP-102 and 0.3% for vehicle at day 84 (p < 0.0001). The most common AEs in the VP-102 group were application site blistering, pruritus, pain, and erythema, which were generally mild or moderate in severity.

Conclusions

Pooled analyses showed a significantly higher percentage of participants with complete molluscum lesion clearance and larger reductions in lesion counts with VP-102 than with vehicle. AEs were anticipated because of the pharmacodynamic properties of cantharidin.

Trial registration

ClinicalTrials.gov identifiers: NCT03377790 (first posted 19 December 2017) and NCT03377803 (first posted 19 December 2017). Video abstract: Pooled Results of Two Randomized Phase III Trials Evaluating VP 102, a Drug Device Combination Product Containing Cantharidin 0.7% (w/v) for the Treatment of Molluscum Contagiosum (MP4 131293 KB).