INTRODUCTION
Onychomycosis remains a major clinical and therapeutic challenge for dermatologists, podiatrists, and other healthcare professionals. The disease is difficult to treat effectively and is extremely recalcitrant, but the approach has to start with confirming the diagnosis. A progressive disease that starts by affecting only one or two toenails, onychomycosis often spreads to other toenails, and carries increased risk of secondary infection.1 In addition, with relapse or re-infection common occurrences a long-term management strategy is needed if the potential impact of the disease is going to be successfully addressed.2-5
It is not uncommon for patients to struggle with onychomycosis for several years; waiting until it has advanced to a more severe, sometimes debilitating stage, where increased pain and discomfort can lead to difficulty in walking or performing daily activities, before seeking treatment.6,7 Yet many onychomycosis patients will find the prospect of long-term treatment somewhat daunting without effective patient education and ongoing reassurance. In healthy young adults, toenails grow at a rate of 1.62mm per month, therefore a new nail could take over a year to grow fully.8 This rate of growth is often decreased in the presence of peripheral vascular disease, onychomycosis, and in the elderly and patients need to be reminded that the nail does not grow at the same pace as the skin.
While generally accepted that they may demonstrate poor compliance as a result, there are limited data within the scientific literature.9-11 Ultimately, patients seek a normal-looking nail and even with mild onychomycosis they can experience negative social or emotional effects and reduced quality of life due to the aesthetic appearance of their affected toenails.6,12-14 The premature perception by patients that an improvement in their condition is associated with cure impacts compliance,9 when a physician’s long-term goal is to eradicate the causative fungus and prevent relapse.
Our study is a post hoc analysis of two large multicenter studies of the treatment of mild to moderate onychomycosis with topical therapy that aims to provide insights into patient outcomes based on initial disease severity and influencing factors.
METHODS
Two multicenter, randomized, double-blind, vehicle-controlled studies designed to evaluate the efficacy, safety, and tolerability of efinaconazole topical solution, 10% relative to its vehicle in 1655 male and female patients aged 18 to 70 years with mild to moderate toenail onychomycosis.15 Patients who presented with 20%-50% clinical involvement of the target toenail were randomized (3:1) to apply blinded study drug once daily to the toenails for 48 weeks.
In this post hoc analysis, patients were categorized based on their baseline disease severity. Four groups were assessed – those with 20%-29%, 30%-39%, 40%-49%, and ≥50% affected