Safety, Pharmacokinetics, and Efficacy of Efinaconazole 10% Topical Solution for Onychomycosis Treatment in Pediatric Patients

September 2020 | Volume 19 | Issue 9 | Original Article | 867 | Copyright © September 2020


Published online August 24, 2020

Lawrence F. Eichenfield , Boni Elewski , Jeffrey L. Sugarman , Ted Rosen , Tracey C. Vlahovic , Aditya K. Gupta , Linda Stein Gold , Radhakrishnan Pillai , Eric Guenin

aDepartments of Dermatology and Pediatrics; University of California, San Diego School of Medicine and Rady Children’s Hospital, San Diego, CA bUniversity of Alabama at Birmingham School of Medicine, Birmingham, AL cUniversity of California, San Francisco, CA dBaylor College of Medicine, Houston, TX eTemple University School of Podiatric Medicine, Philadelphia, PA fMediprobe Research Inc., London, ON, CAN and University of Toronto, Toronto, ON, CAN gHenry Ford Hospital, Detroit, MI hBausch Health US*, LLC, Petaluma, CA iOrtho Dermatologics*, Bridgewater, NJ *Bausch Health US, LLC is an affiliate of Bausch Health Companies Inc. Ortho Dermatologics is a division of Bausch Health US, LLC.

Abstract
Background: Pediatric onychomycosis management is challenging as there are limited treatment options. The objective of this study was to evaluate efinaconazole 10% topical solution in children with onychomycosis.

Methods
: This phase 4, multicenter, open-label study (NCT02812771) evaluated safety, pharmacokinetics (PK), and efficacy of efinaconazole 10% topical solution in pediatric participants (6-16 years). Efinaconazole was administered once daily for 48 weeks, with a 4-week posttreatment follow up. Participants had culture-positive, mild-to-severe distal lateral subungual onychomycosis affecting at least 20% of at least 1 great toenail. The PK subset included participants 12-16 years with moderate-to-severe onychomycosis affecting at least 50% of each great toenail and onychomycosis in at least 4 additional toenails.

Results
: Of 62 enrolled participants, 60 were included in the safety population and 17 in the PK population. Efinaconazole 10% topical solution was well tolerated. The concentration-time profiles for efinaconazole and its major metabolite were relatively stable, with only minor fluctuations during the 24-hour dosing interval. Systemic exposure to efinaconazole was low. By week 52, 65.0% of participants achieved mycologic cure, with a 36.7% mycologic cure rate observed as early as week 12. A total of 40.0% of participants achieved complete cure, 50.0% achieved clinical efficacy, and 88.3% achieved fungal cure by week 52.

Conclusion
: Efinaconazole was safe and efficacious in pediatric participants with mild-to-severe onychomycosis, with improved mycologic cure and complete cure rates compared with adults from two 52-week studies.

J Drugs Dermatol. 2020;19(9):867-872. doi:10.36849/JDD.2020.5401

INTRODUCTION

Onychomycosis—a chronic and recurring fungal infection of the fingernails or toenails—can occur in children, ranging in prevalence from 0.35%–5.5% worldwide.1 Though less common in children than adults,1 onychomycosis has been reported to be responsible for approximately 15% of all nail dystrophies in children.2 Onychomycosis of the toenail can result in permanent toenail deformity, discomfort, and interference with wearing shoes and walking.3

Treatment of onychomycosis is challenging due to the deep location of the infection under the densely keratinized nail plate and can require systemic antifungals for prolonged periods of time.4 However, parents and healthcare practitioners are hesitant to treat young children with a systemic drug that requires laboratory monitoring and can have systemic toxicities5; additionally, oral antifungal agents are not FDA approved for onychomycosis in children. Due to their thinner, faster-growing nails, children are theoretically more likely to respond to topical monotherapy than adults and are therefore good candidates for topical antifungal therapy.5 Currently, there are 3 topical treatments approved for pediatric use: ciclopirox 8% in children ≥12 years of age (generic), tavaborole 5% (Kerydin®, PharmaDerm, Melville, NY) in children ≥6 years of age, and efinaconazole 10% (Jublia®, Ortho Dermatologics, Bridgewater, NJ) in children ≥6 years of age.