Masseter Muscle ProminencePhase 3MMP US P3 417NCT06399718
A Study to Assess BOTOX Injections for the Change of Masseter Muscle Prominence in Adult Participants
A Phase 3 study testing BOTOX in people with Masseter Muscle Prominence, run by AbbVie at 20 sites in United States.
Trial summary
The masseter muscle is one of the muscles in the lower face used for chewing. The prominence of the masseter muscle can appear as a widened lower face which some individuals deem as aesthetically undesirable and can be treated by selectively weakening the masseter muscles with small quantities of botulinum toxin. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Masseter Muscle Prominence
- What is being tested?
- BOTOX
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 207 participants
- Where
- 20 sitesUnited States
- Study dates
- 30 Apr 2024to 10 Nov 2025
- Phase
- Phase 3
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Participant meets the following criteria:
- Bilateral Grade 4 or Grade 5 Masseter Muscle Prominence (MMP) (identical grades for left and right sides of the face), as determined by the investigator using the Masseter Muscle Prominence Scale (MMPS).
- Bilateral Grade 4 or Grade 5 MMP (identical grades for left and right sides of the face), as determined by the participant using the Masseter Muscle Prominence Scale - Participant (MMPS-P).
- Investigator and participant scoring of MMPS and MMPS-P must be the same.
- Body mass index (BMI) ≤ 30 kg/m^2 using the calculation: BMI = weight (kg)/height (m)^2.
Who cannot join
- Excess lower facial fat, jowling, loose or lax skin in lower face, or parotid gland prominence that could interfere with MMPS or MMPS-P grading.
- Asymmetry of left and right sides of the face that could prevent identical MMPS or MMPS-P grading on both sides of the face.
- History of or current temporomandibular disorder (TMJD), or presence of signs/symptoms of possible TMJD.
Trial locations and contacts
20 sites in 1 country.
20 sites in 1 country
United States20 sites
Kavali Plastic Surgery and Skin Renewal Center /ID# 248480
Atlanta, Georgia, 30328
Westlake Dermatology & Cosmetic Surgery - Westlake /ID# 249875
Austin, Texas, 78746-4720
DermResearch Inc. /ID# 248227
Austin, Texas, 78759
Aesthetic Center at Woodholme /ID# 248481
Baltimore, Maryland, 21208-6391
DelRicht Research /ID# 250313
Baton Rouge, Louisiana, 70809
Steven Fagien MD Aesthetic Eyelid Plastic Surgery /ID# 248478
Boca Raton, Florida, 33431-6465
DeNova Research /ID# 248237
Chicago, Illinois, 60610
Michigan Center for Research Corporation /ID# 249145
Clinton Township, Michigan, 48038
Skin Research Institute LLC /ID# 248230
Coral Gables, Florida, 33146-1837
Austin Institute for Clinical Research at SBA Dermatology /ID# 248228
Houston, Texas, 77056-4129
Westside Aesthetics /ID# 248232
Los Angeles, California, 90025-1708
The Practice of Brian S. Biesman MD PLLC /ID# 248226
Nashville, Tennessee, 37203
Sherman Aesthetic Center /ID# 248482
Nashville, Tennessee, 37205-2205
Etre Cosmetic Dermatology and Laser Center /ID# 248229
New Orleans, Louisiana, 70130-4353
Laser & Skin Surgery Center of New York /ID# 248479
New York, New York, 10016-4974
Luxurgery /ID# 248236
New York, New York, 10021
Private Practice - Dr. Steven G. Yoelin /ID# 268046
Newport Beach, California, 92663
Skin Specialists /ID# 248233
Omaha, Nebraska, 68144
Pacific Clinical Innovations /ID# 248231
Vista, California, 92083-6030
Sherber + RAD /ID# 248894
Washington D.C., District of Columbia, 20005-5002
About this study
Official title: BOTOX® (onabotulinumtoxinA) for the Reduction of Masseter Muscle Prominence: A Phase 3, Multicenter, Randomized, Double-Blind, Placebo-Controlled Study
The masseter muscle is one of the muscles in the lower face used for chewing. The prominence of the masseter muscle can appear as a widened lower face which some individuals deem as aesthetically undesirable and can be treated by selectively weakening the masseter muscles with small quantities of botulinum toxin. The purpose of this study is to assess how safe and effective injection of onabotulinumtoxinA (BOTOX) is in adult participants with Masseter Muscle Prominence (MMP).
BOTOX is being investigated for the treatment of Muscle Masseter Prominence. In Period 1, participants are placed in 1 of 2 groups, called treatment arms. Each group receives a different treatment, placebo or BOTOX. There is a 1 in 4 chance that participants will be assigned to placebo. In Period 2, eligible participants can receive an optional open-label retreatment of BOTOX. Approximately 200 adult participants with MMP will be enrolled in the study at approximately 20 sites in the United States.
Read more
Participants will receive intramuscular injections across both the right and left masseter muscle of either BOTOX or placebo on Day 1. Participants who are eligible for re-treatment will be given a BOTOX injection on either the Day 180, 210, 240, or 270 visit and will be followed up for up to 6 months.
There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular monthly visits during the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, checking for side effects, and completing questionnaires.
- Conditions
- Masseter Muscle Prominence
- Being tested
- BOTOX, Placebo
- Keywords
- BOTOX, OnabotulinumtoxinA, Masseter Muscle Prominence
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
BOTOXDrug
Also called OnabotulinumtoxinA
Intramuscular Injections
PlaceboDrug
Intramuscular Injections
| Study group | Role | What they receive |
|---|---|---|
| Double-Blind Period: BOTOX | Experimental | Participants will receive BOTOX injections across both the right and left masseter muscle on Day 1. Receives: Drug: BOTOX |
| Double-Blind Period: Placebo | Placebo comparator | Participants will receive placebo injections across both the right and left masseter muscle on Day 1. Receives: Drug: Placebo |
| Open-Label Period: BOTOX | Experimental | Participants who are eligible for re-treatment will receive BOTOX injections on either the Day 180, 210, 240, or 270 visit and will be followed for up to 6 months. Receives: Drug: BOTOX |
What is being measured
The primary outcome is the main question the study is designed to answer.
Composite Achievement of MMP Severity Improvement and at Least a 2-Grade Improvement from Baseline by Both Investigator-Rated MMPS and Participant-Rated MMPS-P
The investigator and participant each assessed the participant's Masseter Muscle Prominence (MMP) using the Masseter Muscle Prominence Scale (MMPS) and the Masseter Muscle Prominence Scale-Participant (MMPS-P), respectively. Both are a 5-point masseter muscle severity scale with grades ranging from 1 (minimal/not at all noticeable) to 5 (very marked/extremely noticeable).
Measured: Day 90
Number of Participants with Adverse Events (AEs)
An AE is defined as any untoward medical occurrence in a patient or clinical investigation participant administered a pharmaceutical product which does not necessarily have a causal relationship with this treatment.
Measured: Baseline to Day 360
Secondary outcomes (5)
Percentage of Participants who Responded as "Very satisfied" or "Satisfied" on the Lower Facial Shape Questionnaire - Treatment Satisfaction Assessment (LFSQ-TXSAT)
The LFSQ-TXSAT measures satisfaction with the effect of treatment using a 5-point scale ranging from 'Very satisfied' to 'Very dissatisfied.'
Measured: Day 90
Percentage of Participants who Responded as "Not at all bothered" or "A little bothered" on the Bother Impact Assessment for Masseter Muscle Prominence (BIA-MMP)
The BIA-MMP is a single item evaluation of how bothered the participant is by the appearance of their lower face using a 5-point scale from 'Not at all bothered' to 'Extremely bothered.'
Measured: Day 90
Change from Baseline in Lower Facial Shape Questionnaire-Impact Assessment (LFSQ-IA) Summary Score
The LFSQ-IA measures psychosocial impact due to the appearance of the lower face. The LFSQ-IA summary score ranges from '0 (best)' to '24 (worst).'
Measured: Baseline to Day 90
Percentage of Participants Achieving Investigator-Rated MMPS Improvement Over Time
The investigator assessed the participant's MMP using the MMPS, a 5-point masseter muscle severity scale with grades ranging from 1 (minimal) to 5 (very marked).
Measured: Baseline to Day 360
Percentage of Participants Achieving Participant-Rated MMPS-P Improvement Over Time
The investigator assessed the participant's MMP using the MMPS-P, a 5-point masseter muscle severity scale with grades ranging from 1 (not at all noticeable) to 5 (extremely noticeable).
Measured: Baseline to Day 360
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 May 2024
- Study start30 Apr 2024
- Primary completion10 Nov 2025
- Study completion10 Nov 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Masseter Muscle ProminenceStudies of the same condition, open and under way.
- More trials run by AbbVieThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Sequential
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 207 participants (actual)
Sponsor and investigators
- Lead sponsor
- AbbVie
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- ABBVIE INC., Study director, AbbVie
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06399718
- Sponsor's protocol ID
- M21-417
- Acronym
- MMP US P3 417
- Status last verified
- Aug 2026
- First submitted
- 1 May 2024
- Last updated
- 12 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: AbbVie is committed to responsible clinical trial data sharing. This includes access to anonymized, individual and trial-level data (analysis data sets), as well as other information.
Study at a glance
From the registry record, last updated by the sponsor on 12 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- BOTOX® (onabotulinumtoxinA) for the Reduction of Masseter Muscle Prominence: A Phase 3, Multicenter, Randomized, Double-Blind, Placebo-Controlled Study
- ClinicalTrials.gov ID
- NCT06399718
- Acronym / sponsor ID
- MMP US P3 417 / M21-417
- Conditions
- Masseter Muscle Prominence
- Keywords
- BOTOX, OnabotulinumtoxinA, Masseter Muscle Prominence
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 207 participants (actual)
- Lead sponsor
- AbbVieIndustry (pharma, biotech, devices)
- Study start
- 30 Apr 2024 (actual)
- Primary completion
- 10 Nov 2025 (actual)
- Study completion
- 10 Nov 2025 (actual)
- First posted
- 6 May 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The masseter muscle is one of the muscles in the lower face used for chewing. The prominence of the masseter muscle can appear as a widened lower face which some individuals deem as aesthetically undesirable and can be treated by selectively weakening the masseter muscles with small quantities of botulinum toxin. The purpose of this study is to assess how safe and effective injection of onabotulinumtoxinA (BOTOX) is in adult participants with Masseter Muscle Prominence (MMP).
BOTOX is being investigated for the treatment of Muscle Masseter Prominence. In Period 1, participants are placed in 1 of 2 groups, called treatment arms. Each group receives a different treatment, placebo or BOTOX. There is a 1 in 4 chance that participants will be assigned to placebo. In Period 2, eligible participants can receive an optional open-label retreatment of BOTOX. Approximately 200 adult participants with MMP will be enrolled in the study at approximately 20 sites in the United States.
Participants will receive intramuscular injections across both the right and left masseter muscle of either BOTOX or placebo on Day 1. Participants who are eligible for re-treatment will be given a BOTOX injection on either the Day 180, 210, 240, or 270 visit and will be followed up for up to 6 months.
There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular monthly visits during the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, checking for side effects, and completing questionnaires.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Sequential
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Double-Blind Period: BOTOX | Experimental | Drug: BOTOXParticipants will receive BOTOX injections across both the right and left masseter muscle on Day 1. |
| Double-Blind Period: Placebo | Placebo comparator | Drug: PlaceboParticipants will receive placebo injections across both the right and left masseter muscle on Day 1. |
| Open-Label Period: BOTOX | Experimental | Drug: BOTOXParticipants who are eligible for re-treatment will receive BOTOX injections on either the Day 180, 210, 240, or 270 visit and will be followed for up to 6 months. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Participant meets the following criteria:
- Body mass index (BMI) ≤ 30 kg/m^2 using the calculation: BMI = weight (kg)/height (m)^2.
Key exclusion criteria (3 listed)
- Excess lower facial fat, jowling, loose or lax skin in lower face, or parotid gland prominence that could interfere with MMPS or MMPS-P grading.
- Asymmetry of left and right sides of the face that could prevent identical MMPS or MMPS-P grading on both sides of the face.
- History of or current temporomandibular disorder (TMJD), or presence of signs/symptoms of possible TMJD.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| BOTOXAlso: OnabotulinumtoxinAIntramuscular Injections | Drug | Double-Blind Period: BOTOX, Open-Label Period: BOTOX |
| PlaceboIntramuscular Injections | Drug | Double-Blind Period: Placebo |
Primary outcome
Composite Achievement of MMP Severity Improvement and at Least a 2-Grade Improvement from Baseline by Both Investigator-Rated MMPS and Participant-Rated MMPS-P
Time frame: Day 90
The investigator and participant each assessed the participant's Masseter Muscle Prominence (MMP) using the Masseter Muscle Prominence Scale (MMPS) and the Masseter Muscle Prominence Scale-Participant (MMPS-P), respectively. Both are a 5-point masseter muscle severity scale with grades ranging from 1 (minimal/not at all noticeable) to 5 (very marked/extremely noticeable).
Number of Participants with Adverse Events (AEs)
Time frame: Baseline to Day 360
An AE is defined as any untoward medical occurrence in a patient or clinical investigation participant administered a pharmaceutical product which does not necessarily have a causal relationship with this treatment.
5 secondary outcomes
Percentage of Participants who Responded as "Very satisfied" or "Satisfied" on the Lower Facial Shape Questionnaire - Treatment Satisfaction Assessment (LFSQ-TXSAT)
Time frame: Day 90
Percentage of Participants who Responded as "Not at all bothered" or "A little bothered" on the Bother Impact Assessment for Masseter Muscle Prominence (BIA-MMP)
Time frame: Day 90
Change from Baseline in Lower Facial Shape Questionnaire-Impact Assessment (LFSQ-IA) Summary Score
Time frame: Baseline to Day 90
Percentage of Participants Achieving Investigator-Rated MMPS Improvement Over Time
Time frame: Baseline to Day 360
Percentage of Participants Achieving Participant-Rated MMPS-P Improvement Over Time
Time frame: Baseline to Day 360
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 12 Aug 2026.
- Individual participant dataSharing planned: Yes. AbbVie is committed to responsible clinical trial data sharing. This includes access to anonymized, individual and trial-level data (analysis data sets), as well as other information.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
ABBVIE INC. study director
AbbVie
20 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing BOTOX in people with Masseter Muscle Prominence, run by AbbVie at 20 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 12 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 20 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Composite Achievement of MMP Severity Improvement and at Least a 2-Grade Improvement from Baseline by Both Investigator-Rated MMPS and Participant-Rated MMPS-P (time frame: Day 90). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 12 Aug 2026.