An Open-Label, Multi-Center, Multiple-Application Pharmacokinetic Study of Naftifine HCl Gel 2% in Pediatric Subjects With Tinea Pedis.

Background: Tinea pedis is the most common superficial fungal infection. Naftifine hydrochloride is a topical antifungal of the allylamine class, displaying fungicidal activity and clinically significant anti-bacterial and anti-inflammatory effects. Clinical data on topical antifungal therapy using naftifine for tinea pedis in a pediatric population is limited.
Objective: To assess trends in efficacy, tolerability, safety, and to quantify the pharmacokinetics (PK) of topical naftifine hydrochloride gel 2% in pediatric subjects with tinea pedis.
Methods: Twenty-eight subjects (22 pediatric and 6 adult controls) were enrolled and treated in the study. Approximately 2 grams of naftifine hydrochloride gel 2% was applied to each foot (4 grams total) for subjects with tinea pedis. Pharmacokinetic blood and urine samples were collected at various time points throughout the study. Efficacy was assessed based on potassium hydroxide, dermatophyte culture, and signs and symptom results at days 7, 14, and 28. Adverse event information was collected routinely.

Results: The rate and extent of systemic exposure among the pediatric and adult control subjects was low. Adverse events were minimal and were not related to treatment. Positive results were observed as early as day 7; however the proportion of subjects achieving success generally increased over time through day 28 in both treatment groups.
Conclusions: Naftifine hydrochloride gel 2% was found to be well tolerated and safe. Trends in clinical benefit were observed throughout the treatment period; however, continued improvement in efficacy rates were observed during the post-treatment period.