A phase 2, randomized, double-blind, placebo-controlled, dose-ranging study to evaluate the efficacy and safety of orally administered VT-1161 in the treatment of recurrent vulvovaginal candidiasis

Abstract

Background: Lanosterol demethylase is an enzyme that is essential for fungal growth and catalyzes an early step in the biosynthetic pathway of ergosterol, which is a sterol that is required for fungal cell membrane formation and integrity. Lanosterol demethylase is the molecular target of the class of drugs referred to as "azole antifungals." VT-1161 is a novel, oral, selective inhibitor of fungal lanosterol demethylase and is being developed for the treatment of recurrent vulvovaginal candidiasis.

Objective: We evaluated the efficacy and safety of 4 dosing regimens of oral VT-1161 compared with placebo in women with recurrent vulvovaginal candidiasis, which was defined as at least 3 symptomatic episodes of acute vulvovaginal candidiasis within a 12-month period.

Study design: Two hundred fifteen women with a documented history of recurrent vulvovaginal candidiasis and who, at screening, were experiencing an episode of acute vulvovaginal candidiasis (acute vulvovaginal candidiasis; composite vulvovaginal signs and symptoms score of ≥3 and a positive potassium hydroxide test for yeast) were enrolled. After treatment of the acute infection with fluconazole, subjects were assigned randomly to 1 of 5 treatment regimens: (1) VT-1161 150 mg once daily for 7 days, then 150 mg once weekly for 11 weeks, followed by a once-weekly dose of placebo for 12 weeks; (2) VT-1161 300 mg once daily for 7 days, then 300 mg once weekly for 11 weeks, followed by a once-weekly dose of placebo for 12 weeks; (3) VT-1161 150 mg once daily for 7 days, then 150 mg once weekly for 23 weeks; (4) VT-1161 300 mg once daily for 7 days, then 300 mg once weekly for 23 weeks; or (5) a matching placebo regimen for 24 weeks. The primary efficacy outcome was the proportion of subjects with ≥1 culture-verified acute vulvovaginal candidiasis episodes through week 48.

Results: In the intent-to-treat population, the proportion of subjects with ≥1 acute vulvovaginal candidiasis episodes ranged from 0-7% across the 4 VT-1161 arms vs 52% in the placebo arm, with all arms achieving statistical significance vs placebo. VT-1161 was well-tolerated with a favorable safety profile, and the incidence of adverse events was lower in all VT-1161 arms compared with placebo. In addition, no patient in any VT-1161 arm discontinued the study early because of an adverse event or laboratory abnormality. There was also no evidence of an adverse effect of VT-1161 on liver function or electrocardiogram recordings.

Conclusion: In this study, VT-1161 was shown to be efficacious and safe in the treatment of patients with recurrent vulvovaginal candidiasis. These data strongly support further clinical investigation of VT-1161 for the treatment of recurrent vulvovaginal candidiasis.

Trial registration: ClinicalTrials.gov NCT02267382.

Keywords: Candida; VT-1161; antifungal; vulvovaginal candidiasis.