{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T02:32:37Z","timestamp":1785465157334,"version":"3.56.0"},"reference-count":24,"publisher":"Oxford University Press (OUP)","issue":"5","license":[{"start":{"date-parts":[[2025,10,15]],"date-time":"2025-10-15T00:00:00Z","timestamp":1760486400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Allergan Aesthetics, an AbbVie company"},{"name":"Shenavia Balcom-Luker"},{"DOI":"10.13039\/100006483","name":"AbbVie Inc","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100006483","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100023970","name":"LLC","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100023970","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Allergan Aesthetics, an AbbVie company"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,4,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Masseter muscle prominence (MMP) may be aesthetically bothersome to some individuals, leading them to seek treatment for a slimmer lower face.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>The aim of this study was to evaluate the safety and efficacy of onabotulinumtoxinA for the treatment of MMP, including patient-reported outcomes (PROs).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This was a prospective, multicenter trial including a randomized, double-blind, placebo-controlled period (Days 1\u2212180) in which adults rated Grade 4 or 5 (marked\/very marked) on the investigator-assessed MMP Scale (MMPS) were randomized to onabotulinumtoxinA 72\u2005U or placebo. Efficacy endpoints were assessed at Day 90. The primary endpoint was \u22652-grade improvement from baseline on the investigator-assessed MMPS. Secondary endpoints included achieving Grade \u22643 on the MMPS and participant-assessed MMPS\u2014Participant (MMPS-P), \u22652-grade improvement on the participant-assessed MMPS-P, and change from baseline in lower-facial width. Outcomes were assessed using validated measures. Adverse events (AEs) were monitored.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Of 376 enrolled participants (onabotulinumtoxinA, n = 283; placebo, n = 93), 310 (82.4%) completed the study. At Day 90, a greater proportion of onabotulinumtoxinA-treated participants vs placebo achieved MMPS \u22652-grade improvement (51.2% vs 2.2%, P &amp;lt; .0001), and more onabotulinumtoxinA-treated participants vs placebo achieved the secondary endpoints (all P &amp;lt; .0001), with a mean lower-facial width reduction of \u22125.24\u2005mm for onabotulinumtoxinA vs \u22120.04\u2005mm for placebo (P &amp;lt; .0001). Participants reported benefits for onabotulinumtoxinA vs placebo in self-perceived change in MMP, treatment satisfaction, and psychosocial impact. Improvements were sustained through Day 180. Most AEs were mild, nonserious, and resolved.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>OnabotulinumtoxinA effectively reduced the appearance of MMP and improved PROs, with effects lasting up to 6 months and a favorable safety profile.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Level of Evidence: 1 (Therapeutic)<\/jats:title>\n                    <jats:p\/>\n                  <\/jats:sec>","DOI":"10.1093\/asj\/sjaf204","type":"journal-article","created":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T13:41:51Z","timestamp":1760449311000},"page":"486-494","source":"Crossref","is-referenced-by-count":2,"title":["OnabotulinumtoxinA Treatment for Masseter Muscle Prominence: 6-Month Safety and Efficacy Results, Including Patient-Reported Outcomes, From a Phase 3, Randomized, Placebo-Controlled, Multiregional Trial"],"prefix":"10.1093","volume":"46","author":[{"given":"Jiaming","family":"Sun","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lei","family":"Wang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Wu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7734-3146","authenticated-orcid":false,"given":"Shannon","family":"Humphrey","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shyi-Gen","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-4799-7455","authenticated-orcid":false,"given":"William","family":"McGillivray","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2903-1703","authenticated-orcid":false,"given":"Shu-Hung","family":"Huang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuguang","family":"Zhang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Grace","family":"Pan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0603-4995","authenticated-orcid":false,"given":"Catherine","family":"Foley","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabeth","family":"Lee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joan-En","family":"Chang-Lin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-1443-1151","authenticated-orcid":false,"given":"Donna 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