Efinaconazole (KP-103) is a triazole antifungal agent and againsts T. mentagrophytes SM-110 and C. albicans ATCC 10231 with MICs of 0.0039 μg/mL and 0.00098 μg/mL, respectively[1]. Efinaconazole has a potent in vitro activity against fungal pathogens including dermatophytes, Candida and Malassezia species[1].

Topical Efinaconazole solution (0.25 to 1%) is dose-dependently effective in treating both dermatophytoses, for 10 guinea pigs with interdigital tinea pedis or tinea corporis is investigated. The follow up study performs on day-30 and day-9 posttreatment demonstrated that the relapse rates for 1% Efinaconazole-treated animals with tinea pedis and for those with tinea corporis are 20 and 30%, respectively. When a single dose of 1% Efinaconazole is applied to the back skin 48 hours before fungal inoculation, 9 of the 10 animals are protected from the dermatophytosis, suggesting that active Efinaconazole is retained in skin tissue for at least 48 hours after dosing[2].

References:
[1]. Tatsumi Y, et al. Mechanism of action of efinaconazole, a novel triazole antifungal agent. Antimicrob Agents Chemother. 2013 May;57(5):2405-9.
[2]. Tatsum Y, et al. KP-103, a novel triazole derivative, is effective in preventing relapse and successfully treating experimental interdigital tinea pedis and tinea corporis in guinea pigs. Microbiol Immunol. 2002;46(7):425-32.