ACKNOWLEDGEMENTS: Medical writing support was provided by Prescott Medical Communications Group (Chicago, IL) with financial support from Ortho Dermatologics; Ortho Dermatologics is a division of Bausch Health US, LLC • Presented at the PA & NP Fall Clinical Dermatology Conference • June 9-11, 2023 • Orlando, FL Monthly Usage of Efinaconazole 10% Solution in Two Phase 3 Randomized Trials: Is One 4-mL Bottle Enough for Proper Treatment? Steven R Feldman, MD, PhD1; Shari R Lipner, MD, PhD2; Tracey C Vlahovic, DPM3; Warren S Joseph, DPM4; C Ralph Daniel, MD5; Boni Elewski, MD6, Phebe Rich, MD7 1Wake Forest School of Medicine, Winston-Salem, NC; 2Weill Cornell Medicine, New York, NY; 3Temple University School of Podiatric Medicine, Philadelphia, PA; 4Arizona College of Podiatric Medicine, Midwestern University, Glendale, AZ; 5University of Mississippi Medical Center, Jackson, MS; 6University of Alabama at Birmingham School of Medicine, Birmingham, AL; 7Oregon Health and Science University, Portland, OR SYNOPSIS � Topical therapies for onychomycosis require extended treatment durations, and incomplete or intermittent treatment can contribute to high rates of reinfection or relapse1 � Excellent adherence to treatment is necessary to maximize efficacy,2 and prescribing an adequate quantity of medication is essential for good adherence � Efinaconazole 10% topical solution—an azole antifungal used to treat onychomycosis in patients aged 6 years and older—is available in 4- or 8-mL bottles � In the absence of data on patient characteristics influencing the amount of efinaconazole needed, 87% of efinaconazole prescriptions in 2022 were written for one 4-mL bottle per month3 OBJECTIVES � To determine monthly efinaconazole usage by baseline patient demographics and clinical characteristics METHODS � Two identical, double-blind, phase 3 studies (NCT01008033; NCT01007708) enrolled adult participants (18–70 years; N=1655) with mild-to-moderate distal lateral subungual onychomycosis affecting 20–50% of ≥1 great (target) toenail4 � Participants were randomized (3:1) to treatment with efinaconazole 10% solution or vehicle, self-applied once daily for 48 weeks � Bottles of study product (10 mL) were weighed upon dispensation at each study visit (every 4 weeks) and upon return at the following visit � Monthly efinaconazole use was analyzed post hoc based on the total number of affected toenails and percent involvement of the target toenail at baseline as well as body mass index (BMI) and sex RESULTS � At baseline, efinaconazole-treated participants in both studies (N=656 and 580) had on average over one-third involvement of their target toenails (36.2% and 36.7%) and 3.7–3.8 affected toenails4 � Among efinaconazole-treated participants with usage data for this analysis (n=1067), 85% had target toenail involvement of ≥25%, and over 55% had ≥4 affected toenails � As expected, percent involvement of the target toenail, BMI, or sex did not significantly impact average monthly efinaconazole usage (Figure 1) � Among participants with ≥2 affected toenails (90%), average monthly efinaconazole usage was equivalent to 1.10–1.59 4-mL bottles per month (Figure 2) • Only participants with one affected toenail used <4 mL of efinaconazole monthly • For patients with 6 affected toenails, one 4-mL bottle of efinaconazole would provide an average of 19 days of treatment FIGURE 1. Monthly Efinaconazole Use by Baseline Severity at Target (Great) Toenail, BMI, and Sex 0 P ro d u ct U se d ( m L) 14 16 12 10 8 6 4 2 ≥30 349 25 to <30 423 <25 293 BMI (kg/m2) Male 823 Female 244 Sex ≥25% 908159 <25% n= Target Nail Involvement Average number of 4-mL bottles needed (monthly): 4.69 5.23 4.81 5.29 5.26 4.71 5.28 Monthly medication use was calculated by converting mean daily use (in grams) to monthly use (in mL) using a 30-day month and the density of efinaconazole 10% solution. Data are presented as mean ± standard deviation. Diamonds indicate maximum monthly usage for each group. Dashed line indicates usage above which more than one 4-mL bottle would be needed per month. BMI, body mass index. FIGURE 2. Monthly Efinaconazole Use by Number of Affec ted Toenails 0 P ro d u ct U se d ( m L) 14 16 12 10 8 6 4 2 n= Number of Toenails Treated Average number of 4-mL bottles needed (monthly): 107 1 3.10 196 2 4.39 164 3 4.74 206 4 5.52 204 5 5.78 190 6 6.36 Monthly medication use was calculated by converting mean daily use (in grams) to monthly use (in mL) using a 30-day month and the density of efinaconazole 10% solution. Data are presented as mean ± standard deviation. Diamonds indicate maximum monthly usage for each group. Dashed line indicates usage above which more than one 4-mL bottle would be needed per month. CONCLUSIONS � In this large sample of patients with onychomycosis, most had 2 or more affected toenails and used on average more than 4 mL of efinaconazole per month � In contrast, almost 90% of patients in clinical practice are prescribed only one 4-mL bottle monthly, demonstrating a potential disconnect between product need and amount provided to patients � Most patients with onychomycosis of ≥2 toenails may find that one 4-mL bottle of medication runs out in less than a month, leaving gaps in treatment until prescriptions can be refilled • This may prolong time to achieve clinical effects and increase the likelihood of relapse or reinfection1 � Given that nail percent involvement, sex, and BMI do not affect medication usage, number of affected nails should be the major consideration when determining monthly efinaconazole quantity to prescribe • Clinicians should consider prescribing the larger 8-mL bottle of efinaconazole to patients with onychomycosis of more than one affected toenail REFERENCES 1. LaSenna CE and Tosti A. Patient Pref Adherence. 2015;9:887–891. 2. Lipner SR and Ko D. Cutis. 2018;102(6):389–390. 3. Ortho Dermatologics. Data on File. 2022. 4. Elewski BE, et al. J Am Acad Dermatol. 2013;68(4):600–608. AUTHOR DISCLOSURES Steven R Feldman has received research, speaking and/or consulting support from BMS, Eli Lilly and Company, GlaxoSmithKline/Stiefel, AbbVie, Janssen, Alovtech, vTv Therapeutics, Bristol-Myers Squibb, Samsung, Pfizer, Boehringer Ingelheim, Amgen, Dermavant, Arcutis, Novartis, Novan, UCB, Helsinn, Sun Pharma, Almirall, Galderma, Leo Pharma, Mylan, Celgene, Ortho Dermatologics, Menlo, Merck & Co, Qurient, Forte, Arena, Biocon, Accordant, Argenx, Sanofi, Regeneron, the National Biological Corporation, Caremark, Teladoc, Eurofins, Informa, UpToDate and the National Psoriasis Foundation. He is founder and part owner of Causa Research and holds stock in Sensal Health. Shari R. Lipner has served a consultant for Ortho Dermatologics, Hoth Therapeutics, Moberg Pharmaceuticals, and BelleTorus Corporation. Tracey C Vlahovic has served as investigator and speaker for Ortho Dermatologics. Warren S Joseph has served as consultant and speaker for Ortho Dermatologics. C Ralph Daniel has provided clinical research support to Ortho Dermatologics and owns stock in Medimetriks Pharmaceuticals. Boni Elewski has provided clinical research support (research funding to University) for AbbVie, Anaptys-Bio, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Incyte, LEO Pharma, Lilly, Merck, Menlo, Novartis, Pfizer, Regeneron, Sun Pharma, Ortho Dermatologics, and Vanda; and as consultant (received honorarium) from Boehringer Ingelheim, Bristol Meyers Squibb, Celgene, LEO Pharma, Lilly, Menlo, Novartis, Pfizer, Sun Pharma, Ortho Dermatologics, and Verrica. Phoebe Rich has received research and educational grants from AbbVie, Allergan, Anacor Pharmaceuticals, Boehringer Ingelheim, Cassiopea, Dermira, Eli Lilly, Galderma, Janssen Ortho Inc., Kadmon Corporation, LEO Pharma, Merck, Moberg Derma, Novartis, Pfizer, Ranbaxy Laboratories Limited, Sandoz, Viamet Pharmaceutical Inc., Innovation Pharmaceuticals (Cellceutix), and Cutanea Life Sciences.