Information Efinaconazole Efinaconazole (KP-103) is an inhibitor of 14 alpha-demethylase which is involved in the biosynthesis of ergosterol, a constituent of fungal cell membranes. Targets 14 alpha-demethylase In vitro In in vitro antifungal susceptibility tests, efinaconazole shows lower minimum inhibitory concentration (MIC) than terbinafine, ciclopirox, itraconazole and amorolfine. In vivo Efinaconazole is a topical antifungal, so it has relatively low systemic accumulation. The plasma half-life after 10 days of administration is 29.9 h. It has high plasma protein-binding affinity from 95.8 to 96.5%; primarily to albumin, a1-acid glycoprotein and γ-globulin. Efinaconazole is metabolized extensively through oxidative and reductive processes resulting in a sole H3 metabolite. It may also undergo glucuronidation. Efinaconazole does not have significant interactions with CYP450 enzymes in the liver. CYP2C8, CYP2C9, CYP2C19 and CYP3A4 are inhibited by efinaconazole at concentrations higher than the systemic concentrations achieved clinically.