Abstract: Novel Expanded Safe Zone System for Treatment of Submental Fullness with ATX-101 (Deoxycholic Acid)

Abstract

INTRODUCTION: Deoxycholic acid is approved for minimally invasive treatment of submental fat. Most standard markings treat only a small central area of submental fullness to avoid complications, especially marginal mandibular nerve paresis.1,2 This one-size-fits-all approach likely undertreats fuller necks. Knowledge of the submental fat pads provides an anatomical basis for patient-customized treatment with deoxycholic acid.3,4 This study shows the first real-world use of a novel Expanded Safe Zone (ESZ) system and to characterize its safety profile. METHODS: A retrospective review was conducted of 121 patients treated at a single-center between June 2015-December 2016. Each patient was assessed for change in neck anatomy in each of the six regions of the ESZ system, thereby identifying the preplatysmal fat target treatment regions. Deoxycholic acid was injected into each respective region (0.2 mL per injection of 10mg/mL to achieve a dose of 2mg/cm2) for a maximum of 6 treatments. Response was defined as decreased palpable and/or visible fullness due to decreased overall adipose deposits. Injection-site adverse events (AEs) and other AEs were recorded at each visit. RESULTS: Improvement in submental fullness was achieved in 97.5% of patients with follow-up (n=79). AEs included bruising (11.9%), localized tenderness (100%, mean 3.9 days), edema (99.3%, mean 7.7 days), numbness (99.1%, mean 27.6 days), nausea (0.01%), vomiting (0%), headache (2.5%), localized alopecia (5.8%), and paresis (5.8%, mean 27.1 ± 10.1 days, median 30 days, maximum 37 days). CONCLUSION: Postinjection tenderness, edema, and numbness had a higher incidence in this study than pivotal studies (69.5%, 60.4%, 13.8%, respectively),5 likely due to increased area treated and increased dose per treatment, but were transient and resolved in a similar time period (<30 days). Paresis had a similar incidence rate compared to pivotal studies (5.8% vs. 4.3%), but had a shorter median duration (30 days vs. 42 days). This study shows real-world feasibility and initial safety and efficacy using the ESZ for submental fat reduction. This individualized treatment plan is likely to result in better outcomes than a one-size-fits-all approach without increasing adverse events. Reference Citations: 1. Dayan SH, Jones DH, Carruthers J, et al. A Pooled Analysis of the Safety and Efficacy Results of the Multicenter, Double-Blind, Randomized, Placebo-Controlled Phase 3 REFINE-1 and REFINE-2 Trials of ATX-101, a Submental Contouring Injectable Drug for the Reduction of Submental Fat. Plast Reconstr Surg. 2014;134:123. 2. Brackeen A. A template for estimating doses of deoxycholic acid for submental fat fullness. J Am Acad Dermatol. 2016;75(4):e151-e152. 3. Hatef DA, Koshy JC, Sandoval SE, Echo AP, Izaddoost SA, Hollier LH. The submental fat compartment of the neck. Semin Plast Surg. 2009;23(4):288–291. 4. Pilsl U, Anderhuber F. The chin and adjacent fat compartments. Dermatol Surg. 2010;36(2):214–218. 5. Kythera Biopharmaceuticals I. Dermatologic and ophthalmic drugs advisory committee briefing document: ATX-101 (deoxycholic acid) injection. https://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/Drugs/DermatologicandOphthalmicDrugsAdvisoryCommittee/UCM436604.pdf. Accessed February 26, 2017.