title: Antifungal agents for onychomycosis: new treatment strategies to improve safety.
abstract: Onychomycosis is a common and difficult-to-treat fungal infection of the nail unit that gradually leads to dystrophic changes of the nail plate and nail bed. If untreated, infection progresses and may lead to discomfort, reduced quality of life, and risk of complications in patients with comorbid conditions (eg, diabetes, human immunodeficiency virus, peripheral vascular disease). Onychomycosis treatments are designed to eradicate causative pathogens (most commonly Trichophyton rubrum and Trichophyton mentagrophytes), restore healthy nails, and prevent recurrence or spread of infection. Given the deep-seated nature of most cases of onychomycosis, an effective antifungal agent needs to achieve and maintain sufficient drug concentrations throughout the nail unit for the duration of healthy nail in-growth. Oral antifungal drugs are the most effective available therapy and are generally well tolerated, but may be limited by safety concerns and the potential for drug-drug interactions (DDIs). Thus, treating physicians and pharmacists must be cognizant of a patient's current medications; indeed, it may not be feasible to treat onychomycosis in patients with diabetes, heart disease, or depression because of the risk for DDIs. Current topical therapy is not associated with risk of DDIs. Tavaborole and efinaconazole, two recently approved topical agents, have demonstrated good nail penetration and high negative culture rates in clinical trials of patients with onychomycosis. This article provides the treating physician and pharmacist with information on the safety and effectiveness of current oral (allylamine, azole) and topical (ciclopirox, efinaconazole, tavaborole) treatment to aid in making informed treatment decisions based on the unique characteristics (medication history, comorbidities, nature of onychomycosis) of each patient.
authors.affiliation: Anacor Pharmaceuticals, Inc.. lzane@anacor.com.
authors.forename: Lee T
authors.initials: LT
authors.lastname: Zane
authors.forename: Sanjay
authors.initials: S
authors.lastname: Chanda
authors.forename: Dina
authors.initials: D
authors.lastname: Coronado
authors.forename: James
authors.initials: J
authors.lastname: Del Rosso
mesh_terms: D000284:Administration, Oral; D000287:Administration, Topical; D000935:Antifungal Agents / Q000009:adverse effects*; D001896:Boron Compounds / Q000009:adverse effects; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000009:adverse effects; D056486:Chemical and Drug Induced Liver Injury / Q000209:etiology*; D000077768:Ciclopirox; D065690:Cytochrome P-450 CYP2D6 Inhibitors / Q000009:adverse effects*; D065692:Cytochrome P-450 CYP3A Inhibitors / Q000009:adverse effects*; D004347:Drug Interactions; D006801:Humans; D017964:Itraconazole / Q000009:adverse effects; D009281:Naphthalenes / Q000009:adverse effects; D014009:Onychomycosis / Q000188:drug therapy*; D011728:Pyridones / Q000009:adverse effects; D000077291:Terbinafine; D014230:Triazoles / Q000009:adverse effects
chemical_list: D000935:Antifungal Agents; D001896:Boron Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D065690:Cytochrome P-450 CYP2D6 Inhibitors; D065692:Cytochrome P-450 CYP3A Inhibitors; D009281:Naphthalenes; D011728:Pyridones; D014230:Triazoles; D000077768:Ciclopirox; D017964:Itraconazole; D000077291:Terbinafine; C431707:efinaconazole; C512998:tavaborole