Author:
Sugiura Keita,Sugimoto Noriaki,Hosaka Shinya,Katafuchi-Nagashima Maria,Arakawa Yoshio,Tatsumi Yoshiyuki,Jo Siu William,Pillai Radhakrishnan
Abstract
ABSTRACTOnychomycosis is a common fungal nail disease that is difficult to treat topically due to the deep location of the infection under the densely keratinized nail plate. Keratin affinity of topical drugs is an important physicochemical property impacting therapeutic efficacy. To be effective, topical drugs must penetrate the nail bed and retain their antifungal activity within the nail matrix, both of which are adversely affected by keratin binding. We investigated these properties for efinaconazole, a new topical antifungal for onychomycosis, compared with those of the existing topical drugs ciclopirox and amorolfine. The efinaconazole free-drug concentration in keratin suspensions was 14.3%, significantly higher than the concentrations of ciclopirox and amorolfine, which were 0.7% and 1.9%, respectively (P< 0.001). Efinaconazole was released from keratin at a higher proportion than in the reference drugs, with about half of the remaining keratin-bound efinaconazole removed after washing. In single-dosein vitrostudies, efinaconazole penetrated full-thickness human nails into the receptor phase and also inhibited the growth ofTrichophyton rubrumunder the nail. In the presence of keratin, efinaconazole exhibited fungicidal activity againstTrichophyton mentagrophytescomparable to that of amorolfine and superior to that of ciclopirox. In a guinea pig onychomycosis model withT. mentagrophytesinfection, an efinaconazole solution significantly decreased nail fungal burden compared to that of ciclopirox and amorolfine lacquers (P< 0.01). These results suggest that the high nail permeability of efinaconazole and its potent fungicidal activity in the presence of keratin are related to its low keratin affinity, which may contribute to its efficacy in onychomycosis.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Pharmacology (medical),Pharmacology
Reference26 articles.
1. Epidemiological survey of foot diseases in Japan: results of 30,000 foot checks by dermatologists;Watanabe;J. Dermatol.,2010
2. A large-scale North American study of fungal isolates from nails: the frequency of onychomycosis, fungal distribution, and antifungal susceptibility patterns;Ghannoum;J. Am. Acad. Dermatol.,2000
3. Onychomycosis. Treatment, quality of life, and economic issues;Elewski;Am. J. Clin. Dermatol.,2000
4. Progress on new therapeutics for fungal nail infections;Baker;Annu. Rep. Med. Chem.,2005
5. Single-blind, randomized, prospective study on terbinafine and itraconazole for treatment of dermatophyte toenail onychomycosis in the elderly;Gupta;J. Am. Acad. Dermatol.,2001
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