Research Triangle Park, NC-based Viamet Pharmaceuticals in January reported positive results from its Phase 2b randomized controlled trial of VT-1161 for onychomycosis of the large toenail. VT-1161 is a novel, once-weekly, oral antifungal drug.
The investigators assigned 259 patients to one of five study arms: 300 mg of VT-1161 once weekly for 12 weeks, then 12 weeks of placebo; 600 mg of VT-1161 once weekly for 12 weeks, followed by 12 weeks of placebo; either 300 or 600 mg of the antifungal agent once weekly for the full 24 weeks; or 24 weeks of once-per-week placebo.
At baseline, mean distal lateral subungual onychomycosis involvement of the large toenail was 46%; the average number of toenails affected was 4.6 across the trial arms.
The primary endpoint was complete cure at week 48, which required complete clinical cure and negative mycology. Patients were also evaluated for complete cure at week 60.
In the intent-to-treat analysis, complete cure rates at 48 weeks were 0% in the placebo arm and 32% to 42% in the four VT-1161 arms, with all arms achieving statistical significance versus placebo. In the per protocol analysis, cure rates were as high as 55% in the VT-1161 groups. There was an 87% median reduction in the percentage of nail involvement at week 48 across the VT-1161 arms, compared with a 9% reduction in the placebo arm (all arms reached statistical significance vs placebo).
Complete cure rates continued to improve through week 60, and all active arms had a complete cure rate greater than 40% in the intent-to-treat analysis. No patient in any VT-1161 arm discontinued the study due to a laboratory abnormality, and fewer than 1% dropped out because of an adverse event. There was also no evidence of an adverse effect of VT-1161 on liver function.