Econazole Nitrate Foam 1% for the Treatment of Tinea Pedis: Results from Two Double-Blind, Vehicle-Controlled, Phase 3 Clinical Trials

July 2014 | Volume 13 | Issue 7 | Original Article | 803 | Copyright © July 2014

Boni E. Elewski MDa and Tracey C. Vlahovic DPMb

aDepartment of Dermatology, University of Alabama at Birmingham, Birmingham, AL
bDepartment of Podiatric Medicine, Temple University, Philadelphia, PA

Abstract
BACKGROUND: Econazole nitrate is a broad-spectrum topical antifungal with activity against a variety of dermatophytes and yeasts. A new topical dosage form, econazole nitrate topical foam 1%, utilizing patented Proderm Technology® has been developed for treatment of interdigital tinea pedis.
OBJECTIVE: To evaluate econazole nitrate foam 1% versus foam vehicle for treatment of interdigital tinea pedis.
METHODS: Two randomized, double-blind, parallel-group, vehicle-controlled, multicenter studies enrolled males and females ≥12 years old with a clinical diagnosis of interdigital tinea pedis and baseline fungal culture positive for a dermatophyte. Subjects applied econazole nitrate foam 1% (n=246) or foam vehicle (n=249) once daily for 4 weeks. The primary endpoint was proportion of subjects achieving a complete cure (negative KOH, negative fungal culture, complete resolution of all signs and symptoms) at 2 weeks post-treatment (Day 43). Secondary endpoints included mycologic cure (negative KOH and negative culture) and effective treatment (mycologic cure + no or mild erythema and/or scaling and all other signs and symptoms absent).
RESULTS: The complete cure rate at Day 43 was 24.3% for econazole nitrate foam 1% vs 3.6% for foam vehicle. In addition, higher rates of mycologic cure (67.6% vs 16.9%) and effective treatment (48.6% vs 10.8%) were observed with econazole nitrate foam 1% versus the foam vehicle. There were few adverse events and only nasopharyngitis and headache were experienced by >1% of subjects. No serious adverse events were reported for econazole nitrate foam 1%.
CONCLUSIONS: Econazole nitrate foam 1% exhibited superiority over foam vehicle for the primary and secondary endpoints with a high mycologic cure rate for all pathogens evaluated. Econazole nitrate foam 1% was safe and well tolerated with a safety profile comparable with the foam vehicle. Econazole nitrate foam 1% presents a novel alternative for the management of tinea pedis.

J Drugs Dermatol. 2014;13(7):803-808.

INTRODUCTION

Tinea pedis is estimated to be the second most common skin condition in the United States, behind acne. Up to 15% of the population may manifest the disease. 1 The ideal treatment for superficial mycoses includes the use of topical antimycotics. This is true for all superficial mycoses (eg, tinea pedis), unless the infection involves an extensive area or is resistant to initial therapy. The antimycotics of choice for topical and systemic mycoses include azoles, allylamines, thiocarbamates, polyenes, 5-fluorocytosine, candins, griseofulvin, and oxaboroles.2 Azole antifungal agents are used frequently in the treatment of tinea pedis. They have broad-spectrum antifungal activity and are also active against some gram-positive bacteria.3
Econazole nitrate is a broad-spectrum topical antifungal agent with known activity against a variety of dermatophytes and yeasts including Epidermophyton floccosum, Microsporum audouinii, M gypseum, M canis, Trichophyton rubrum, T mentagrophytes, T tonsurans, Candida albicans, Malassezia furfur, and certain gram-positive bacteria.4-10
For >20 years econazole nitrate has demonstrated efficacy for a variety of superficial fungal infections including tinea pedis, tinea corporis, tinea cruris, tinea versicolor, and cutaneous candidiasis, with an excellent safety and tolerability profile.6,9,11-14
A new topical dosage form, econazole nitrate foam 1%, intended for the treatment of interdigital tinea pedis, recently received US Food and Drug Administration approval. This novel dosage form, using patented Proderm Technology®, is easy to apply, disperses quickly, and does not leave a residue. Proderm Technology is a water-lipid based dermal delivery