Botulinum Toxin Type A (BOTOX®) Treatment of Masseter Muscle Hypertrophy

Phase 2

Completed

Brief Summary: This study will evaluate the safety and efficacy of a range of doses of botulinum toxin Type A (BOTOX®) for the treatment of patients with bilateral Masseter Muscle Hypertrophy (MMH).

Recruitment & Eligibility

Inclusion Criteria

-Participants with Masseter Muscle Hypertrophy

Exclusion Criteria

Diagnosis of Myasthenia gravis, Eaton-Lambert syndrome, amyotrophic lateral sclerosis, or any other condition that might interfere with neuromuscular function
Prior botulinum toxin treatment of any serotype to the masseter muscle or lower face
History of dental or surgical procedure for lower facial shaping or masseter muscle reduction
History of or current temporomandibular joint disorder (TMJD)

Arm && Interventions

Group	Intervention	Description
BOTOX® 48U	botulinum toxin Type A	Botulinum Toxin Type A (BOTOX®) 48U total dose administered intramuscularly to the bilateral masseter muscles on Day 1 and retreatment at Day 180 if applicable.
BOTOX® 24U	botulinum toxin Type A	Botulinum Toxin Type A (BOTOX®) 24U total dose administered intramuscularly to the bilateral masseter muscles on Day 1 and retreatment at Day 180 if applicable.
Placebo	Normal saline	Placebo (Normal saline) administered intramuscularly to the bilateral masseter muscles on Day 1 and retreatment at Day 180 if applicable.
BOTOX® 72U	botulinum toxin Type A	Botulinum Toxin Type A (BOTOX®) 72U total dose administered intramuscularly to the bilateral masseter muscles on Day 1 and retreatment at Day 180 if applicable.
BOTOX® 96U	botulinum toxin Type A	Botulinum Toxin Type A (BOTOX®) 96U total dose administered intramuscularly to the bilateral masseter muscles on Day 1 and retreatment at Day 180 if applicable.

Primary Outcome Measures

Name	Time	Method
Change From Baseline in Lower Facial Volume Using VECTRA 3D Images	Baseline (Day 1) to Day 90 of Treatment Cycle 1	Lower facial volume was calculated from 3-dimensional (3D) images captured with the VECTRA M3 3D Stereophotogrammetry imaging system and was analyzed using computer assisted systems and predetermined facial landmarks. The difference in volume was measured between the select region of the baseline surface 3D model and the select region of the posttreatment surface 3D model. A negative change from Baseline (decrease in volume) indicates improvement.

Secondary Outcome Measures

Name	Time	Method
Percentage of Participants Who Achieved a Masseter Muscle Prominence Scale (MMPS) Grade ≤ 3 as Assessed by the Investigator	Day 90 of Treatment Cycle 1	The investigator used visual inspection and palpation to grade the prominence of the participant's masseter muscle on the left and right sides of the face using the MMPS where: 1=minimal prominence (best), 2=mild prominence, 3=moderate prominence, 4=marked prominence, 5=very marked prominence (worst). The percentage of participants with grade 3 or less is reported.

Locations (14): Central Sydney Dermatology
🇦🇺
Sydney, New South Wales, Australia
The Rose Medical & Aesthetic Centre
🇦🇺
North Fremantle, Western Australia, Australia
Dr. Shannon Humphrey Inc.
🇨🇦
Vancouver, British Columbia, Canada
Dr. Jean Carruthers Cosmetic Surgery, Inc.
🇨🇦
Vancouver, British Columbia, Canada
Kaohsiung Medical University Hospital
🇨🇳
Kaohsiung, Taiwan
Taipei Chang Gung Memorial Hospital of CGMF
🇨🇳
Taipei, Taiwan
Tri-Service General Hospital
🇨🇳
Taipei, Taiwan
National Taiwan University Hospital
🇨🇳
Taipei, Taiwan
Project Skin MD
🇨🇦
Vancouver, British Columbia, Canada
Pacific Dermaesthetics
🇨🇦
Vancouver, British Columbia, Canada
Arthur Swift Research Inc.
🇨🇦
Montreal, Quebec, Canada
Shape Clinic
🇦🇺
Darlinghurst, New South Wales, Australia
Esteem Beauty & Day Spa
🇦🇺
Main Beach, Queensland, Australia
Bertucci MedSpa
🇨🇦
Woodbridge, Ontario, Canada