Oteseconazole (VT-1161) for the Management of Dermatophyte Toenail Onychomycosis: A Review of Phase II Trial Subgroup Efficacy and Extended Follow-Up Safety

Oteseconazole, a synthetic tetrazole antifungal, provides pharmacological advantages that suggest it can be a safe and effective treatment for Trichophyton rubrum onychomycosis. A Phase II study of oteseconazole (VT-1161) for onychomycosis demonstrated good efficacy and safety up to Week 60 in the dosing regimens tested: 300 mg for 12 weeks; 300 mg for 24 weeks; 600 mg for 12 weeks and 600 mg for 24 weeks (all given once daily for 2 weeks, then once weekly for remaining weeks). Additional analysis of efficacy was performed using patient factors that can impact onychomycosis. Similar efficacy rates were found across all four regimens tested. Patient factors (<50 years of age, <50% affected nail area) were more strongly associated with improved outcomes than dose escalation of oteseconazole but did not necessarily predict better overall outcomes. No significant safety concerns were found up to Week 60. New extended follow-up data from Week 60 to Week 96 demonstrated long-term plasma retention of oteseconazole with no additional oteseconazole-related adverse events. Accordingly, clinical photographic assessment at Weeks 72 and 96 showed improvement in the target toenail; however, the number of evaluable patients was limited (n = 22), and mycology testing was not performed. The tetrazole structure of oteseconazole significantly reduces the risk of drug–drug interaction compared to traditional azoles (itraconazole, fluconazole). The favorable safety and efficacy profile suggests oteseconazole could be a potential alternative to itraconazole for onychomycosis at any of the tested doses.