JUBLIA Solution Ref.[10228] Active ingredients: Efinaconazole

The pharmacodynamics of JUBLIA is unknown.

Systemic absorption of efinaconazole in 18 adult subjects with severe onychomycosis was determined after application of JUBLIA once daily for 28 days to patients' 10 toenails and 0.5 cm adjacent skin. The concentration of efinaconazole in plasma was determined at multiple time points over the course of 24-hour periods on Days 1, 14, and 28. Efinaconazole mean ± SD plasma C_max on Day 28 was 0.67 ± 0.37 ng/mL and the mean ± SD AUC was 12.15 ± 6.91 h•ng/mL. The plasma concentration versus time profile at steady state was generally flat over a 24-hour dosing interval. In a separate study of healthy volunteers, the plasma half-life of efinaconazole following daily applications when applied to all 10 toenails for 7 days was 29.9 hours.

Specific Populations

Pediatric patients

PK of efinaconazole was assessed in 17 pediatric subjects 12 to <17 years of age with moderate to severe onychomycosis following application of JUBLIA once daily to all 10 toenails for 28 days.

The plasma concentrations of efinaconazole in pediatric subjects were relatively flat over a 24-hour dosing interval. The mean ± SD plasma C_max and AUC_0-24 for efinaconazole on Day 28 were 0.55±0.38 ng/mL and 11.4±7.68 h•ng/mL, respectively.

Drug Interactions

JUBLIA is considered a non-inhibitor of the CYP450 enzyme family. In in vitro studies using human liver microsomes, efinaconazole did not inhibit CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2PE1 and CYP3A4 enzyme activities at expected clinical systemic concentrations. In vitro studies in human primary hepatocytes showed that efinaconazole did not induce CYP1A2 or CYP3A4 activities.

Mechanism of Action

Efinaconazole is an azole antifungal. Efinaconazole inhibits fungal lanosterol 14α-demethylase involved in the biosynthesis of ergosterol, a constituent of fungal cell membranes.

Activity In Vitro and In Vivo

Efinaconazole has been shown to be active against isolates of the following microorganisms, both in vitro and in clinical infections. Efinaconazole exhibits in vitro minimum inhibitory concentrations (MICs) of 0.06 mcg/mL or less against most (≥90%) isolates of the following microorganisms:

• Trichophyton rubrum
• Trichophyton mentagrophytes

Mechanism of Resistance

Efinaconazole drug resistance development was studied in vitro against T. mentagrophytes, T. rubrum and C. albicans. Serial passage of fungal cultures in the presence of subgrowth inhibitory concentrations of efinaconazole increased the MIC by up to 4-fold. The clinical significance of these in vitro results is unknown.

A 2-year dermal carcinogenicity study in mice was conducted with daily topical administration of 3%, 10% and 30% efinaconazole solution. Severe irritation was noted at the treatment site in all dose groups, which was attributed to the vehicle and confounded the interpretation of skin effects by efinaconazole. The high dose group was terminated at Week 34 due to severe skin reactions. No drug-related neoplasms were noted at doses up to 10% efinaconazole solution (248 times the MRHD based on AUC comparisons).

Efinaconazole revealed no evidence of mutagenic or clastogenic potential based on the results of two in vitro genotoxicity tests (Ames assay and Chinese hamster lung cell chromosome aberration assay) and one in vivo genotoxicity test (mouse peripheral reticulocyte micronucleus assay).

No effects on fertility were observed in male and female rats that were administered subcutaneous doses up to 25 mg/kg/day efinaconazole (279 times the MRHD based on AUC comparisons) prior to and during early pregnancy. Efinaconazole delayed the estrous cycle in females at 25 mg/kg/day but not at 5 mg/kg/day (56 times MRHD based on AUC comparisons).

The safety and efficacy of once-daily use of JUBLIA for the treatment of onychomycosis of the toenail were assessed in two 52-week prospective, multicenter, randomized, double-blind clinical trials in subjects 18 years and older (18 to 70 years of age) with 20% to 50% clinical involvement of the target toenail, without dermatophytomas or lunula (matrix) involvement. The trials compared 48 weeks of treatment with JUBLIA to the vehicle solution. The Complete Cure rate was assessed at Week 52 (4 weeks after completion of therapy). Complete cure was defined as 0% involvement of the target toenail (no clinical evidence of onychomycosis of the target toenail) in addition to Mycologic Cure, defined as both negative fungal culture and negative KOH. Table 2 lists the efficacy results for trials 1 and 2.

Table 2. Efficacy Endpoints:

^a Complete cure defined as 0% clinical involvement of the target toenail plus negative KOH and negative culture.
^b Complete or almost complete cure defined as ≤5% affected target toenail area involved and negative KOH and culture.
^c Mycologic cure defined as negative KOH and negative culture.