INTRODUCTION AND PRIOR TREATMENT
Onychomycosis—a fungal infection of the nail bed or plate caused by dermatophytes, non-dermatophyte molds, or yeasts—affects up to 14% of individuals in North America.1,2 It is undertreated3 and treatment is challenging as toenail growth can take up to 12 months or more,4,5 the infection is frequently located under the keratinized nail plate,6 and disease recurrence is common.5 Oral medications are generally efficacious, but there are safety concerns such as drug-drug interactions, smell/taste disturbances, allergic reactions, or possible liver toxicity.7,8 In addition, there may be evidence of recent emergence of antifungal resistance to terbinafine.9,10
For diagnosis and testing, prior guidelines and consensus publications on onychomycosis treatment have noted that in addition to clinical examination, confirmatory laboratory testing should be performed using one or more of the following: microscopic examination (eg, potassium hydroxide [KOH], periodic acid-Schiff test [PAS]), or fungal culture.11-16 While polymerase chain reaction (PCR) techniques were considered useful for confirming diagnosis, they were deemed not cost effective enough for general use.12-14,16
For pharmaceutical treatments administered orally, terbinafine was considered first-line and was preferred over itraconazole.1,12 While fluconazole is not approved for onychomycosis treatment in the US, it was considered an alternative to terbinafine or itraconazole.12 Griseofulvin was generally not recommended due to low efficacy and high recurrence rates compared with other oral antifungal agents.12 Oral medications were recommended for severe cases,14,15 though some oral drugs were to be avoided or required caution when used in patients with certain comorbidities or concomitant medications.1,12
Topical medications (ciclopirox, tavaborole, efinaconazole) were recommended for pediatric patients13,14 and adults with mild-to-moderate disease (20%–60%, <50%, or <65% involvement),1,11,13-15 especially those taking concomitant medications or with other
For diagnosis and testing, prior guidelines and consensus publications on onychomycosis treatment have noted that in addition to clinical examination, confirmatory laboratory testing should be performed using one or more of the following: microscopic examination (eg, potassium hydroxide [KOH], periodic acid-Schiff test [PAS]), or fungal culture.11-16 While polymerase chain reaction (PCR) techniques were considered useful for confirming diagnosis, they were deemed not cost effective enough for general use.12-14,16
For pharmaceutical treatments administered orally, terbinafine was considered first-line and was preferred over itraconazole.1,12 While fluconazole is not approved for onychomycosis treatment in the US, it was considered an alternative to terbinafine or itraconazole.12 Griseofulvin was generally not recommended due to low efficacy and high recurrence rates compared with other oral antifungal agents.12 Oral medications were recommended for severe cases,14,15 though some oral drugs were to be avoided or required caution when used in patients with certain comorbidities or concomitant medications.1,12
Topical medications (ciclopirox, tavaborole, efinaconazole) were recommended for pediatric patients13,14 and adults with mild-to-moderate disease (20%–60%, <50%, or <65% involvement),1,11,13-15 especially those taking concomitant medications or with other