6.1 Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

In two clinical trials, 791 subjects were treated with KERYDIN. The most commonly reported adverse reactions are listed below (Table 1).

6.2 Postmarketing Experience

The following adverse reactions have been identified during postmarketing use of KERYDIN. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug product exposure:

Hypersensitivity; contact allergy

8.1 Pregnancy

8.2 Lactation

8.4 Pediatric Use

The safety and efficacy of KERYDIN were established in patients 6 years of age and older. Use of KERYDIN in these age groups is supported by evidence from adequate and well-controlled studies of KERYDIN in adults with additional data from an open-label pharmacokinetics study of tavaborole in subjects 12 years to less than 17 years old [see Clinical Pharmacology (12.3)].

8.5 Geriatric Use

In clinical trials of 791 subjects who were exposed to KERYDIN, 19% were 65 years of age and over, while 4% were 75 years of age and over. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, but greater sensitivity of some older individuals cannot be ruled out.

12.1 Mechanism of Action

KERYDIN is an oxaborole antifungal [see Clinical Pharmacology (12.4)].

12.2 Pharmacodynamics

At therapeutic doses, KERYDIN is not expected to prolong QTc to any clinically relevant extent.

12.3 Pharmacokinetics

Tavaborole undergoes extensive metabolism. Renal excretion is the major route of elimination of the metabolites.

In a clinical pharmacology trial of six healthy adult male volunteers who received a single topical application of 5% 14C-tavaborole solution, tavaborole conjugates and metabolites were shown to be excreted primarily in the urine.

The pharmacokinetics (PK) of tavaborole was investigated in 24 adult subjects with distal subungual onychomycosis involving at least 4 toenails (including at least 1 great toenail) following a single dose and a 2-week daily topical application of 200 μL of a 5% solution of tavaborole to all ten toenails and 2 mm of skin surrounding each toenail. Steady state was achieved after 14 days of dosing. After a single dose, the mean (± standard deviation) peak concentration (Cmax) of tavaborole was 3.5 ± 2.3 ng/mL (n=21 with measurable concentrations, range 0.618–10.2 ng/mL, LLOQ=0.5 ng/mL), and the mean AUClast ± SD was 44.4 ± 25.5 ng*hr/mL (n=21). After 2 weeks of daily dosing, the mean Cmax ± SD was 5.2 ± 3.5 ng/mL (n=24, range 1.5–12.8 ng/mL), and the mean AUCτ ± SD was 75.8 ± 44.5 ng*hr/mL.

In another study PK of tavaborole was investigated in 22 subjects aged 12 years to less than 17 years with distal subungual onychomycosis involving at least 4 toenails (including at least 1 great toenail with at least 20% involvement) following once daily application of 5% solution of tavaborole to all ten toenails and 2 mm of skin surrounding each toenail for 29 days. On Day 29, the mean ± SD Cmax was 5.9 ± 4.9 ng/mL (n=21 with measurable concentrations, range 1.0 –16.4 ng/mL, LLOQ=0.5 ng/mL), and the mean ± SD AUC0-24 was 76.0 ± 62.5 ng*hr/mL.

12.4 Microbiology

13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility

In an oral carcinogenicity study in Sprague-Dawley rats, oral doses of 12.5, 25, and 50 mg/kg/day tavaborole were administered to rats once daily for 104 weeks. No drug related neoplastic findings were noted at oral doses up to 50 mg/kg/day tavaborole (14 times the MRHD based on AUC comparisons).

In a dermal carcinogenicity study in CD-1 mice, topical doses of 5%, 10%, and 15% tavaborole solution were administered to mice once daily for 104 weeks. No drug related neoplastic findings were noted at topical doses up to 15% tavaborole solution (89 times the MRHD based on AUC comparisons).

Tavaborole revealed no evidence of mutagenic or clastogenic potential based on the results of two in vitro genotoxicity tests (Ames assay and Human lymphocyte chromosomal aberration assay) and one in vivo genotoxicity test (rat micronucleus assay).

No effects on fertility were observed in male and female rats that were administered oral doses up to 300 mg/kg/day tavaborole (107 times the MRHD based on AUC comparisons) prior to and during early pregnancy.

16.1 How Supplied

KERYDIN (tavaborole) topical solution, 5% is a clear, colorless solution supplied in an amber glass bottle with a screw cap. At initial use, the screw cap is replaced with the dropper assembly.

KERYDIN (tavaborole) topical solution, 5% is supplied in the following presentations:

NDC 10337-905-10: One bottle containing 10 mL of solution with one glass pointed-tip dropper.

NDC 10337-905-44: One bottle containing 4 mL of solution with one glass pointed-tip dropper.

16.2 Storage and Handling

Store at 20–25°C (68–77°F); excursions permitted to 15–30°C (59–86°F) [see USP Controlled Room Temperature].
CAUTION: Flammable. Keep away from heat and flame.
Discard product within 3 months after insertion of the dropper.
Keep bottle tightly closed. Keep out of reach of children.