Masseter Muscle ProminencePhase 3MMP EU P3NCT06068855
A Study to Assess the Effectiveness of BOTOX (Botulinum Toxin Type A) 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 27 sites in 7 countries.
Trial summary
The masseter muscle is one of the muscles in the lower face used for chewing. Prominence of the masseter muscle can appear as a widened and square lower face shape, which is an aesthetic concern for individuals who prefer a narrower and more ovoid lower face shape. 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
- 249 participants
- Where
- 27 sitesin 7 countries
- Study dates
- 17 Oct 2023to 20 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
- Body mass index < 30 kg/m^2 using the calculation: BMI = weight (kg)/height (m)^2, rounded to the nearest whole number.
- Participants meets the following criteria:
- Bilateral Grade 4 or Grade 5 MMP (identical grades for left and right side of the face), as determined at screening and at the Day 1 visit by the investigator using the MMPS.
- Bilateral Grade 4 or Grade 5 MMP (identical grades for left and right sides of the face), as determined at the Day 1 visit by the participant using the MMPS-P.
- MMP grades, as assessed by investigator and participant, do not need to be identical but have to be a minimum of Grade 4 with bilateral symmetry at Day 1.
- Participants who responded "A lot" or "Extremely" bothered by the appearance of their MMP as measured by the Bother Impact Assessment for Masseter Muscle Prominence (BIA-MMP) and attain a total score of ≥ 15 on the Lower Facial Shape Questionnaire - Impact Assessment (LFSQ-IA), determined at the Day 1 visit.
Who cannot join
- Has current intraoral infection, including infection of the mouth or gums, or facial skin infection requiring medical treatment in the opinion of the investigator.
- Has weakness of the masseter, pterygoid, or temporalis muscles due to trauma, facial nerve injury, or other condition that could interfere with normal chewing and jaw clenching, as determined by the investigator.
- 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, as determined by the investigator.
- Has medical condition that may put the participant at increased medical risk with exposure to BOTOX, including diagnosed myasthenia gravis, Eaton-Lambert syndrome, amyotrophic lateral sclerosis, or any other condition that might interfere with neuromuscular function.
- History of dental or surgical procedure for lower facial shaping or masseter muscle reduction.
- History of any soft tissue fillers in the jawline.
- Has prior exposure to botulinum toxin of any serotype to any part of the body (not including masseter muscle) within the 3 months prior to Day 1.
- History of or current TMJD, or presence of signs/symptoms of possible TMJD in the opinion of the investigator.
Trial locations and contacts
27 sites in 7 countries.
27 sites in 7 countries
Germany5 sites
Hautzentrum Koeln /ID# 247502
Cologne, North Rhine-Westphalia, 50996
Privatpraxis Dr. Hilton & Partner /ID# 246602
Düsseldorf, North Rhine-Westphalia, 40212
Universitaet Hamburg /ID# 247503
Hamburg, 20146
Hautok and Hautok-cosmetics /ID# 246600
Munich, Bavaria, 80333
Studienzentrum Theatiner46 /ID# 246601
Munich, Bavaria, 80333
Belgium4 sites
Da Vinci Clinic /ID# 246731
Beerse, Antwerpen, 2340
Universitair Ziekenhuis Brussel /ID# 246311
Jette, Brussels Capital, 1090
Lightfalls Clinic /ID# 247335
Melle, Oost-Vlaanderen, 9090
Evolve Clinic /ID# 246729
Schilde, Antwerpen, 2970
France4 sites
Mediti /Id# 246875
Antibes, 06160
Cabinet Dermatologie et Esthetique /ID# 246871
Cannes, 06400
Cabinet médical /ID# 246873
Paris, 75007
Cabinet de Chirurgie Plastique et Esthétique /ID# 246872
Toulouse, 31000
Spain4 sites
Grupo Pedro Jaen /ID# 246485
Madrid, 28006
Clinica Robega /ID# 252239
Madrid, 28008
Clinica Alejandria /ID# 247380
Valencia, Valencia, 46004
Gavín Dermatólogos /ID# 252120
Vigo, Pontevedra, 36201
United Kingdom4 sites
Waverley Medical Practice /ID# 246432
Coatbridge, North Lanarkshire, ML5 3AP
Dr Nestor's Medical Cosmetic Centre /ID# 246437
Edinburgh, EH3 6RS
Interface Aesthetics Training Limited /ID# 248115
London, W1H 6AZ
MediZen /ID# 246431
Sutton Coldfield, B74 2UG
Bulgaria3 sites
Dermavist - Group Practice for Specialized Medical Care for Skin Disease /ID# 247630
Plovdiv, 4000
Medical Center Derma Vita EOOD /ID# 247327
Sofia, 1407
Medical Centre Dermatology Dr. Denkova EOOD /ID# 246591
Sofia, 1700
Italy3 sites
Azienda Unita Sanitaria Locale Latina /ID# 246835
Latina, 04100
Fondazione Policlinico Universitario Campus Bio-Medico /ID# 246836
Roma, 00128
CRC - Centro Ricerche Cliniche di Verona S.r.l. /ID# 246834
Verona, 37134
About this study
Official title: BOTOX® (Botulinum Toxin Type A) 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. Prominence of the masseter muscle can appear as a widened and square lower face shape, which is an aesthetic concern for individuals who prefer a narrower and more ovoid lower face shape. Treatments are available for masseter muscle prominice (MMP), but researchers are looking for new non-surgical treatments. This study will assess adverse events and effectiveness of BOTOX in adult participants with MMP.
BOTOX is being investigated for the treatment of MMP. Participants are placed in 1 of 2 groups, called treatment arms. Each group receives a different treatment. There is 1 in 4 chance that participants will be assigned to placebo. Around 248 adult participants with MMP will be enrolled in the study at approximately 30 sites in Europe.
Read more
Participants will receive either BOTOX or Placebo administered as 6 intramuscular injections to the masseter on Day 1. Participants who are eligible for retreatment will be given BOTOX on Day 180 and will be followed 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 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
- Masseter Muscle Prominence, BOTOX, Botulinum Toxin Type A
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
BOTOXDrug
Also called Botulinum Toxin Type A
Intramuscular Injections
PlaceboDrug
Intramuscular Injections
| Study group | Role | What they receive |
|---|---|---|
| Double-Blind Period: Botox | Experimental | Participants will receive 6 intramuscular injections of BOTOX to the masseter on Day 1. Receives: Drug: BOTOX |
| Open-Label Period: Botox | Experimental | Participants who are eligible for retreatment will be given open-label BOTOX on Day 180 and will be followed for up to 6 months Receives: Drug: BOTOX |
| Double Blind Period: Placebo | Placebo comparator | Participants will receive 6 intramuscular injections of Placebo to the masseter on Day 1. Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Achievement of 2-grade or more improvement from baseline on the Masseter Muscle Prominence Scale (MMPS) as assessed by the Investigator
The investigator assessed the severity of the participant's MMP using the MMPS 5-point scale where: 1=minimal (best), 2=mild, 3=moderate, 4=marked, and 5=very marked (worst).
Measured: Day 90
Achievement of 2-grade or more improvement from baseline on the Masseter Muscle Prominence Scale - Participant (MMPS-P) as assessed by the Participant
The participant assessed the severity of their MMP using the MMPS-P 5-point scale where: 1=not at all pronounced (best), 2=mildly pronounced, 3=moderately pronounced, 4=pronounced, and 5=very pronounced (worst).
Measured: Day 90
Secondary outcomes (5)
Response of "Very Satisfied" or "Satisfied" on the Lower Facial Shape Questionnaire - Treatment Satisfaction Assessment (LFSQ-TXSAT)
The LFSQ-TXSAT measures the participant's satisfaction with the effect of treatment on the appearance of their lower face where 2=Very satisfied, 1=Satisfied, 0=Neither satisfied nor dissatisfied, -1=Dissatisfied, -2=Very dissatisfied.
Measured: Day 90 to Day 180
Response of "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 where 0=Not at all bothered, 1=A little bothered, 2=Somewhat bothered, 3=A lot bothered, 4=Extremely bothered.
Measured: Day 90 to Day 180
Change from baseline in lower facial volume (cm^3)
Lower facial volume is calculated from standardized images
Measured: Day 90
Change from baseline in lower facial width (mm)
Lower facial width is calculated from standardized images
Measured: Day 90
Change from baseline in Lower Facial Shape Questionnaire - Impact Assessment (LFSQ-IA) summary score
The LFSQ-IA is a 6-item assessment that measures psychosocial impact of the appearance of the lower face where 0= Not at all, 1=A little bit, 2=Somewhat, 3=Quite a bit and 4=Extremely.
Measured: Day 90 to Day 180
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Oct 2023
- Study start17 Oct 2023
- Primary completion20 Nov 2025
- Study completion20 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
- 249 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
- NCT06068855
- Sponsor's protocol ID
- M23-123
- Other IDs
- 2022-500568-37-00
- Acronym
- MMP EU P3
- Status last verified
- Dec 2025
- First submitted
- 29 Sep 2023
- Last updated
- 10 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- 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 10 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- BOTOX® (Botulinum Toxin Type A) for the Reduction of Masseter Muscle Prominence: A Phase 3, Multicenter, Randomized, Double-Blind, Placebo-Controlled Study
- ClinicalTrials.gov ID
- NCT06068855
- Acronym / sponsor ID
- MMP EU P3 / M23-123
- Conditions
- Masseter Muscle Prominence
- Keywords
- Masseter Muscle Prominence, BOTOX, Botulinum Toxin Type A
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 249 participants (actual)
- Lead sponsor
- AbbVieIndustry (pharma, biotech, devices)
- Study start
- 17 Oct 2023 (actual)
- Primary completion
- 20 Nov 2025 (actual)
- Study completion
- 20 Nov 2025 (actual)
- First posted
- 5 Oct 2023 (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. Prominence of the masseter muscle can appear as a widened and square lower face shape, which is an aesthetic concern for individuals who prefer a narrower and more ovoid lower face shape. Treatments are available for masseter muscle prominice (MMP), but researchers are looking for new non-surgical treatments. This study will assess adverse events and effectiveness of BOTOX in adult participants with MMP.
BOTOX is being investigated for the treatment of MMP. Participants are placed in 1 of 2 groups, called treatment arms. Each group receives a different treatment. There is 1 in 4 chance that participants will be assigned to placebo. Around 248 adult participants with MMP will be enrolled in the study at approximately 30 sites in Europe.
Participants will receive either BOTOX or Placebo administered as 6 intramuscular injections to the masseter on Day 1. Participants who are eligible for retreatment will be given BOTOX on Day 180 and will be followed 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 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 6 intramuscular injections of BOTOX to the masseter on Day 1. |
| Open-Label Period: Botox | Experimental | Drug: BOTOXParticipants who are eligible for retreatment will be given open-label BOTOX on Day 180 and will be followed for up to 6 months |
| Double Blind Period: Placebo | Placebo comparator | Drug: PlaceboParticipants will receive 6 intramuscular injections of Placebo to the masseter on Day 1. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Body mass index < 30 kg/m^2 using the calculation: BMI = weight (kg)/height (m)^2, rounded to the nearest whole number.
- Participants meets the following criteria:
- Participants who responded "A lot" or "Extremely" bothered by the appearance of their MMP as measured by the Bother Impact Assessment for Masseter Muscle Prominence (BIA-MMP) and attain a total score of ≥ 15 on the Lower Facial Shape Questionnaire - Impact Assessment (LFSQ-IA), determined at the Day 1 visit.
Key exclusion criteria (8 listed)
- Has current intraoral infection, including infection of the mouth or gums, or facial skin infection requiring medical treatment in the opinion of the investigator.
- Has weakness of the masseter, pterygoid, or temporalis muscles due to trauma, facial nerve injury, or other condition that could interfere with normal chewing and jaw clenching, as determined by the investigator.
- 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, as determined by the investigator.
- Has medical condition that may put the participant at increased medical risk with exposure to BOTOX, including diagnosed myasthenia gravis, Eaton-Lambert syndrome, amyotrophic lateral sclerosis, or any other condition that might interfere with neuromuscular function.
- History of dental or surgical procedure for lower facial shaping or masseter muscle reduction.
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: Botulinum Toxin Type AIntramuscular Injections | Drug | Double-Blind Period: Botox, Open-Label Period: Botox |
| PlaceboIntramuscular Injections | Drug | Double Blind Period: Placebo |
Primary outcome
Achievement of 2-grade or more improvement from baseline on the Masseter Muscle Prominence Scale (MMPS) as assessed by the Investigator
Time frame: Day 90
The investigator assessed the severity of the participant's MMP using the MMPS 5-point scale where: 1=minimal (best), 2=mild, 3=moderate, 4=marked, and 5=very marked (worst).
Achievement of 2-grade or more improvement from baseline on the Masseter Muscle Prominence Scale - Participant (MMPS-P) as assessed by the Participant
Time frame: Day 90
The participant assessed the severity of their MMP using the MMPS-P 5-point scale where: 1=not at all pronounced (best), 2=mildly pronounced, 3=moderately pronounced, 4=pronounced, and 5=very pronounced (worst).
5 secondary outcomes
Response of "Very Satisfied" or "Satisfied" on the Lower Facial Shape Questionnaire - Treatment Satisfaction Assessment (LFSQ-TXSAT)
Time frame: Day 90 to Day 180
Response of "Not at all bothered" or "A little bothered" on the Bother Impact Assessment for Masseter Muscle Prominence (BIA-MMP)
Time frame: Day 90 to Day 180
Change from baseline in lower facial volume (cm^3)
Time frame: Day 90
Change from baseline in lower facial width (mm)
Time frame: Day 90
Change from baseline in Lower Facial Shape Questionnaire - Impact Assessment (LFSQ-IA) summary score
Time frame: Day 90 to Day 180
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 10 Dec 2025.
- 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
27 sites in 7 countries: 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 27 sites in 7 countries.
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 6 inclusion and 8 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 10 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 27 sites in Germany, Belgium, France, Spain, United Kingdom and 2 more countries. 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?
Achievement of 2-grade or more improvement from baseline on the Masseter Muscle Prominence Scale (MMPS) as assessed by the Investigator (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 10 Dec 2025.