Naftifine Hydrochloride

1 INDICATIONS AND USAGE NAFTIN ® Gel is an allylamine antifungal indicated for the treatment of interdigital tinea pedis caused by the organisms Trichophyton rubrum , Trichophyton mentagrophytes , and Epidermophyton floccosum . NAFTIN ® Gel is an allylamine antifungal indicated for the treatment of interdigital tinea pedis caused by the organisms Trichophyton rubrum, Trichophyton mentagrophytes, and Epidermophyton floccosum . ( 1 )

2 DOSAGE AND ADMINISTRATION Apply a thin layer of NAFTIN ® Gel once daily to the affected areas plus an approximate ½ inch margin of healthy surrounding skin for 2 weeks. For topical use only. NAFTIN ® Gel is not for ophthalmic, oral, or intravaginal use. Apply a thin layer of NAFTIN ® Gel once daily to the affected areas plus an approximate ½ inch margin of healthy surrounding skin for 2 weeks. ( 2 ) For topical use only. NAFTIN ® Gel is not for ophthalmic, oral, or intravaginal use. ( 2 )

6 ADVERSE REACTIONS The most common adverse reactions are application site reactions (2%). ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Sebela Pharmaceuticals Inc. at 1-888-271-4621 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 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 clinical practice. In two randomized, vehicle-controlled trials, 1143 subjects were treated with NAFTIN ® Gel versus 571 subjects treated with the vehicle. The trial subjects were 12 to 92 years old, were primarily male (76%), and were 59% Caucasian, 38% Black or African American, and 23% Hispanic or Latino. Subjects received doses once daily, topically, for 2 weeks to cover the affected skin areas plus a ½-inch margin of surrounding healthy skin. The most common adverse reactions were application site reactions which occurred at the rate of 2% in NAFTIN Gel arm versus 1% in vehicle arm. Most adverse reactions were mild in severity. In an open-label pediatric pharmacokinetics and safety trial 22 pediatric subjects 12-17 years of age with interdigital tinea pedis received NAFTIN ® Gel. The incidence of adverse reactions in the pediatric population was similar to that observed in adult population. Cumulative irritancy testing revealed the potential for NAFTIN ® Gel to cause irritation. There was no evidence that NAFTIN ® Gel causes contact sensitization, phototoxicity, or photoallergenicity in healthy skin. 6.2 Postmarketing Experience 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 exposure. The following adverse reactions have been identified during post-approval use of naftifine hydrochloride: blisters, burning sensation, crusting, dryness, erythema/redness, inflammation, irritation, maceration, pain, pruritus [mild]/itching, rash and swelling.

12.3 Pharmacokinetics In vitro and in vivo bioavailability studies have demonstrated that naftifine penetrates the stratum corneum in sufficient concentration to inhibit the growth of dermatophytes. Pharmacokinetic analysis of plasma samples from 32 subjects with tinea pedis treated with a mean dose of 3.9 grams NAFTIN ® Gel applied once daily to both feet for 14 days showed increased exposure over the treatment period, with a geometric mean (CV%) AUC 0-24 (area under plasma concentration-versus-time curve from time 0 to 24 hours) of 10.5 (118) ng∙hr/mL on Day 1 and an AUC 0-24 of 70 (59) ng∙hr/mL on Day 14. The accumulation ratio based on AUC was approximately 6. Maximum concentration (C max ) also increased over the treatment period; geometric mean (CV%) C max after a single dose was 0.9 (92) ng/mL on Day 1; C max on Day 14 was 3.7 (64) ng/mL. Median T max was 20.0 hours (range: 8, 20 hours) after a single application on Day 1 and 8.0 hours (range: 0, 24 hours) on Day 14. Trough plasma concentrations increased during the trial period and reached steady state after 11 days. In the same pharmacokinetic trial the fraction of dose excreted in urine during the treatment period was less than or equal to 0.01% of the applied dose. In a second trial, the pharmacokinetics of NAFTIN ® Gel was evaluated in 22 pediatric subjects 12-17 years of age with tinea pedis. Subjects were treated with a mean dose of 4.1 grams NAFTIN ® Gel applied to the affected area once daily for 14 days. The results showed that the systemic exposure increased over the treatment period. Geometric mean (CV%) AUC0-24 was 15.9 (212) ng∙hr/mL on Day 1 and 60.0 (131) ng∙hr/mL on Day 14. Geometric mean (CV%) Cmax after a single dose was 1.40 (154) ng/mL on Day 1 and 3.81 (154) ng/mL on Day 14. The fraction of dose excreted in urine during the treatment period was less than or equal to 0.003% of the applied dose.