CLINICAL PHARMACOLOGY
Mechanism Of Action
LUZU Cream, 1% is an azole antifungal [see Microbiology].
Pharmacodynamics
At therapeutic doses, LUZU Cream, 1% is not expected to
prolong QTc to any clinically relevant extent.
Pharmacokinetics
Luliconazole is the R enantiomer of a chiral molecule.
The potential for interconversion between R and S enantiomers in humans has not
been assessed. Information on the pharmacokinetics of luliconazole presented
below refers to both R enantiomer and S enantiomer, if any, combined.
Luliconazole is >99% protein bound in plasma.
In a PK trial, 12 subjects with moderate to severe tinea
pedis and 8 subjects with moderate to severe tinea cruris applied a mean daily
amount of approximately 3.5 grams of LUZU Cream, 1% to the affected and
surrounding areas once daily for 15 days. Plasma concentrations of luliconazole
on Day 15 were measurable in all subjects and fluctuated little during the
24-hour interval. In subjects with tinea pedis, the mean ± SD of the maximum
concentration (Cmax) was 0.40 ± 0.76 ng/mL after the first dose and 0.93 ± 1.23
ng/mL after the final dose. The mean time to reach Cmax (Tmax) was 16.9 ± 9.39
hours after the first dose and 5.8 ± 7.61 hours after the final dose. Exposure
to luliconazole, as expressed by area under the concentration time curve (AUC0–24),
was 6.88 ± 14.50 ng*hr/mL after the first dose and 18.74 ± 27.05 ng*hr/mL after
the final dose. In subjects with tinea cruris, the mean ± SD Cmax was 4.91 ±
2.51 ng/mL after the first dose and 7.36 ± 2.66 ng/mL after the final dose. The
mean Tmax was 21.0 ± 5.55 hours after the first dose and 6.5 ± 8.25 hours after
the final dose. Exposure to luliconazole, as expressed by AUC0–24, was 85.1 ± 43.69
ng*hr/mL after the first dose and 121.74 ± 53.36 ng*hr/mL after the final dose.
PK data of luliconazole measured in adolescent subjects
(12 to <18 years of age) with moderate to severe interdigital tinea pedis or
moderate to severe tinea cruris as well as in subjects 2 to <18 years of age
with tinea corporis are described in Specific Populations below.
Specific Populations
PK of luliconazole was assessed in 30 adolescent subjects
12 to <18 years of age with moderate to severe interdigital tinea pedis
(N=15) or moderate to severe tinea cruris (N=15). Subjects with tinea pedis
applied approximately 3 grams of LUZU Cream, 1% once daily to the affected area
and adjacent skin for 15 days, while subjects with tinea cruris applied LUZU
Cream, 1% once daily to the affected and adjacent skin for 8 days.
Generally, the systemic exposure of luliconazole was
greater in the subjects with tinea cruris than tinea pedis. In subjects with
tinea pedis, the systemic concentrations of luliconazole were quantifiable in
all the subjects on Day 8 and Day 15. The mean ± SD Cmax was 1.80 ± 1.86 ng/mL
after the first dose on Day 1, and 3.93 ± 1.67 ng/mL and 3.27 ± 1.71 ng/mL on
Days 8 and 15, respectively. The mean ± SD AUC0-24 was 20.47 ± 14.47 ng*hr/mL
after the first dose on Day 1, and 64.94 ± 32.47 ng*hr/mL and 60.38 ± 37.92
ng*hr/mL on Days 8 and Day 15, respectively. Like in adult subjects, the mean
plasma concentrations of luliconazole in adolescent subjects on Days 8 and 15
were similar and fluctuated little during a 24-hour interval.
In subjects with moderate to severe tinea cruris, the
systemic concentrations of luliconazole were quantifiable in all the subjects
on Day 8. The mean ± SD Cmax was 9.80 ± 5.94 ng/mL after the first dose (Day 1)
and 15.40 ± 13.62 ng/mL after the last dose (Day 8). The mean ± SD AUC0-24 was
157.07 ± 92.18 ng*hr/mL and 266.06 ± 236.07 ng*hr/mL, after the first dose (Day
1) and the last dose (Day 8).
In subjects with tinea corporis, the systemic
concentrations of luliconazole were assessed at pre-dose and at 6 hours
post-dose on the last day of treatment following once daily treatment with LUZU
Cream, 1% for 7 days. The systemic concentrations were quantifiable in all the
12 subjects and the mean ± SD daily dose of LUZU Cream, 1% was 2.84 ± 1.82 g.
The mean ± SD concentrations of the of luliconazole at 15 minutes prior to
dosing and at 6 hours post-dose on Day 7 were 4.63 ± 2.93 ng/mL and 4.84 ± 3.33
ng/mL, respectively.
Drug Interactions
Results of in vitro studies indicated that therapeutic
doses of LUZU Cream, 1% did not inhibit cytochrome P450 (CYP) enzymes 1A2, 2C9
and 2D6, but can inhibit the activity of CYP2B6, 2C8, 2C19, and 3A4. The most
sensitive enzyme, CYP2C19, was further evaluated in an in vivo study using
omeprazole as a probe substrate in adult subjects with moderate to severe
interdigital tinea pedis and tinea cruris. The results showed that LUZU Cream,
1% applied at a daily amount of approximately 4 grams increased the omeprazole
systemic exposure (AUC) by approximately 30% compared to the exposure of
omeprazole administered alone. LUZU Cream, 1% is considered a weak inhibitor of
CYP2C19. For tinea cruris, extrapolation from both in vitro inhibition studies
and in vivo data in adults to the adolescent subjects showed that in some
subjects, levels of luliconazole can approach or exceed those required to be a
moderate inhibitor of CYP2C19.
Results of in vitro studies indicated that therapeutic
doses of LUZU Cream, 1% did not induce CYP1A2, 2B6, and 3A4.
Microbiology
Mechanism Of Action
Luliconazole is an antifungal that belongs to the azole
class. Although the exact mechanism of action against dermatophytes is unknown,
luliconazole appears to inhibit ergosterol synthesis by inhibiting the enzyme
lanosterol demethylase. Inhibition of this enzyme's activity by azoles results
in decreased amounts of ergosterol, a constituent of fungal cell membranes, and
a corresponding accumulation of lanosterol.
Mechanism Of Resistance
To date, a mechanism of resistance to luliconazole has
not been described.
LUZU Cream, 1% has been shown to be active against most
isolates of the following fungi, both in vitro and in clinical infections as
described in the INDICATIONS AND USAGE section:
Trichophyton rubrum
Epidermophyton floccosum
Clinical Studies
Interdigital Tinea Pedis
The safety and efficacy of LUZU (luliconazole) Cream, 1%
was evaluated in two randomized, double-blind, vehicle-controlled, multi-center
clinical trials in 423 subjects with a clinical and culture-confirmed diagnosis
of interdigital tinea pedis. Subjects were randomized to receive LUZU Cream, 1%
or vehicle. Subjects applied either LUZU Cream, 1% or vehicle cream to the
entire area of the forefeet including all interdigital web spaces and
approximately 2.5 cm (1 in) of the surrounding area of the foot once daily for
14 days.
The mean age of the study population was 41 years (range
13 to 78 years); 82% were male; 53% were White and 40% were Black or African
American. Signs and symptoms of tinea pedis (erythema, scaling, and pruritus),
KOH exam and dermatophyte culture were assessed at baseline, end-of-treatment
(Day 14), 2 and 4 weeks post-treatment.
Overall treatment success was defined as complete
clearance (clinical cure and mycological cure) at 4 weeks post-treatment. LUZU
Cream, 1% demonstrated complete clearance in subjects with interdigital tinea
pedis. Treatment outcomes at 4 weeks post-treatment are summarized in Table 1.
Table 1: Efficacy Results at 4 Weeks Post-treatment –
Interdigital Tinea Pedis
|
Study 1 |
Study 2 |
LUZU Cream, 1%
N=106
n (%) |
Vehicle Cream
N=103
n (%) |
LUZU Cream,
1%
N=107
n (%) |
Vehicle Cream
N=107
n (%) |
Complete Clearance1 |
28 (26%) |
2 (2%) |
15 (14%) |
3 (3%) |
Effective Treatment2 |
51 (48%) |
10 (10%) |
35 (33%) |
16 (15%) |
Clinical Cure3 |
31 (29%) |
8 (8%) |
16 (15%) |
4 (4%) |
Mycological Cure4 |
66 (62%) |
18 (18%) |
60 (56%) |
29 (27%) |
1 Proportion of subjects who achieved both
clinical cure and mycological cure
2 Negative KOH and culture and at most mild erythema and/or scaling
and no pruritus
3 Absence of erythema, scaling and pruritus
4 Negative KOH and negative fungal culture |
Tinea Cruris
The safety and efficacy of LUZU (luliconazole) Cream, 1%
was evaluated in a randomized, double-blind, vehicle-controlled, multi-center
clinical trial in 256 subjects with a clinical and culture-confirmed diagnosis
of tinea cruris. Subjects were randomized to receive LUZU Cream, 1% or vehicle.
Subjects applied either LUZU Cream, 1% or vehicle cream to the affected area
and approximately 2.5 cm (1 in) of the surrounding area once daily for 7 days.
The mean age of the study population was 40 years (range
14 to 88 years); 83% were male; 58% were White and 34% were Black or African American.
Signs and symptoms of tinea cruris (erythema, scaling, and pruritus), positive
KOH exam and dermatophyte culture were assessed at baseline, end-of-treatment
(Day 7), 2 and 3 weeks post-treatment.
Overall treatment success was defined as complete
clearance (clinical cure and mycological cure) at 3 weeks post-treatment. LUZU
Cream, 1% demonstrated complete clearance in subjects with tinea cruris.
Treatment outcomes at 3 weeks post-treatment are summarized in Table 2.
Table 2: Efficacy Results at 3 Weeks Post-treatment -
Tinea Cruris
|
LUZU Cream, 1%
N=165
n (%) |
Vehicle Cream
N=91
n (%) |
Complete Clearance1 |
35 (21%) |
4 (4%) |
Effective Treatment2 |
71 (43%) |
17 (19%) |
Clinical Cure3 |
40 (24%) |
6 (7%) |
Mycological Cure4 |
129 (78%) |
41 (45%) |
1 Proportion of subjects who achieved both
clinical cure and mycological cure
2 Negative KOH and culture and at most mild erythema and/or scaling
and no pruritus
3 Absence of erythema, scaling and pruritus
4 Negative KOH and negative fungal culture |
Tinea Corporis
The safety and efficacy of LUZU (luliconazole) Cream, 1%
was evaluated in a randomized, double-blind, vehicle-controlled, multi-center
clinical trial in 75 subjects age 2 to <18 years old with a clinical and
culture-confirmed diagnosis of tinea corporis. Subjects were randomized to
receive LUZU Cream, 1% or vehicle cream. Subjects applied either LUZU Cream, 1%
or vehicle cream to the affected area and approximately 2.5 cm (1 in) of the
surrounding skin once daily for 7 days.
The mean age of the study population was 8 years; 72%
were male; 36% were White and 64% were Black or African American. Signs and
symptoms of tinea cruris (erythema, scaling, and pruritus), positive KOH exam
and dermatophyte culture were assessed at baseline, end-of-treatment (Day 7), 2
and 3 weeks post-treatment.
Treatment outcomes at 3 weeks post-treatment are
summarized in Table 3.
Table 3: Efficacy Results at 3 Weeks Post-treatment -
Tinea Corporis
|
LUZU Cream, 1%
N=51
n (%) |
Vehicle Cream
N=14
n (%) |
Complete Clearance1 |
36 (71%) |
5 (36%) |
Effective Treatment2 |
39 (77%) |
8 (57%) |
Clinical Cure3 |
41 (80%) |
6 (43%) |
Mycological Cure4 |
41 (80%) |
8 (57%) |
1 Proportion of subjects who achieved both
clinical cure and mycological cure
2 Negative KOH and culture and at most mild erythema and/or scaling
and no pruritus
3 Absence of erythema, scaling and pruritus
4 Negative KOH and negative fungal culture |