INTRODUCTION
Dermatophyte infections are fungal infections of keratinized
tissue, including the skin, hair, and nails.1 These infections are common, affecting an estimated 10% to 20% of people in the United States and up to 25% of the population worldwide.2 A recent meta-analysis concluded that onychomycosis affects roughly 4% of the population in North America.3 Visits to the doctor to treat dermatophyte infections continue to rise. One study in the U.S. reported 8.8 million visits for tinea corporis, 7.5 million visits for tinea pedis, and 3.6 million
visits for tinea cruris over a 10-year period (1995-2004).4
Similar fungal organisms infect both the skin and the nails. While Epidermophyton floccosum and Trichophyton rubrum are common causes of tinea corporis, tinea pedis, and tinea cruris, T. rubrum is the most prevalent fungal pathogen worldwide.
5,6 Moreover, T. rubrum is responsible for 90% of cases of onychomycosis.7
Dermatophyte infections warrant treatment. They cause primary discomfort and pruritus, and also spread to other body parts and other people. In addition, broken skin serves as an entry site for potential
bacterial superinfections.8,9,10 Onychomycosis in particular should be treated as soon as possible because early intervention yields better outcomes11 and progression can lead to painful nail dystrophy and significantly affect quality of life (QOL).12,13
The American Academy of Dermatology recommends topical therapy for the initial treatment of uncomplicated dermatophyte
infections of the skin.14 While there are many antifungal options available, proper drug selection is important because adherence to the regimen is crucial for achieving a successful
therapeutic outcome.15 Several azole and allylamine class topical antifungal agents are currently commercially available to treat dermatophyte infections. The azole class includes econazole, oxiconazole, sertaconazole, ketoconazole,
sulconazole, and clotrimazole; and the allylamine class includes naftifine, butenafine, and terbinafine.
The azoles are thought to inhibit the synthesis of ergosterol, which affects the permeability of the cell membrane by binding with phospholipids to the fungal cell membrane.16 Allylamines inhibit squalene epoxidase, an essential enzyme in the ergosterol
biosynthesis pathway of fungal cell membrane formation.16 The inhibition of squalene epoxidase results in cellular permeability
and growth inhibition.16
For onychomycosis, topical therapies, namely ciclopirox nail lacquer, had previously been limited, as the available options yielded low efficacy and required frequent nail debridement. Recently, new topical antifungal options have been brought to the market to treat onychomycosis, including topical tavaborole and efinaconazole. New drugs for the treatment of dermatophyte infections include the azole luliconazole and the allylamine naftifine, which are indicated for the treatment of tinea pedis, tinea corporis, and tinea cruris.
Luliconazole
Background Information
Luliconazole is a new antifungal drug developed for the topical
treatment of dermatophyte infections. It has been used in Japan since 2005 and received clearance by the Food and Drug Administration (FDA) in the U.S. in 2013. Its indication is for the topical treatment of interdigital tinea pedis, tinea cruris, and tinea corporis caused by the organisms T. rubrum and E. floccosum in adults. When treating tinea pedis, luliconazole should be administered
once daily for 2 weeks. For tinea corporis and tinea cruris, it should be administered once daily for 1 week.17
An imidazole antifungal, luliconazole is thought to disrupt production
of the fungal cell membrane. While the exact mechanism
