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Trial details imported from

For full trial details, please see the original record at

Registration number
Ethics application status
Date submitted
Date registered
Date last updated

Titles & IDs
Public title
The Safety and Efficacy of vBloc Therapy Delivered by the Maestro Rechargeable System for the Treatment of Obesity
Scientific title
A Randomized, Double Blind Sham Controlled Clinical Trial to Evaluate the Safety and Efficacy of vBloc Therapy Delivered by the Maestro Rechargeable System for the Treatment of Obesity
Secondary ID [1] 0 0
IDE G070025
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 0 0
Condition category
Condition code
Diet and Nutrition 0 0 0 0
Metabolic and Endocrine 0 0 0 0
Other metabolic disorders

Study type
Description of intervention(s) / exposure
Treatment: Devices - vBloc (Active Device)
Treatment: Devices - Sham (Non-active Device)

Active Comparator: vBloc (Active Device) - The treatment group will receive a functional device that will deliver charge to the vagus nerve during the study period

Sham Comparator: Sham (Non-active Device) - The control group will receive a functional, but non-active device that will deliver no charge to the vagus nerve during the study period

Treatment: Devices: vBloc (Active Device)
Active device will deliver vBloc Therapy

Treatment: Devices: Sham (Non-active Device)
Functional non-active control device will deliver no vBloc Therapy

Intervention code [1] 0 0
Treatment: Devices
Comparator / control treatment
Control group

Primary outcome [1] 0 0
Percentage of Subjects Experiencing Implant/Revision Procedure, Device or Therapy Related Serious Adverse Events (SAEs). - To demonstrate that the implant/revision procedure, device and therapy related serious adverse event rate in the vBloc group at 12 months post-implant is significantly lower than 15%.
Timepoint [1] 0 0
12 months
Primary outcome [2] 0 0
Percentage of Excess Weight Loss (EWL) by Body Mass Index (BMI) Method. - Observe at least a 10% greater excess body weight loss (EWL) from randomization with the Maestro System after 12 months of vBloc Therapy compared to Sham by body mass index (BMI) method. (Body mass index is calculated by dividing body weight (kg) by body height (m) squared (BMI=kg/m2)).
Timepoint [2] 0 0
12 months
Primary outcome [3] 0 0
Percentage Responder Rate in the Treatment Arm. - The second co-primary effectiveness endpoint was based on responder rates with the following two requirements: (i) at least 55% of vBloc subjects would achieve a %EWL of at least 20%; and (ii) at least 45% of vBloc subjects would achieve a %EWL of at least 25%.
Timepoint [3] 0 0
12 months

Key inclusion criteria
Inclusion criteria

1. Signed informed consent

2. Body mass index (BMI) = 40 kg/m2 to 45 kg/m2 or BMI = 35 kg/m2 to 39.9 kg/m2 with one
or more obesity related co-morbid conditions. Co-morbid conditions may include one or
more of the following:

- Type 2 diabetes mellitus as defined in inclusion criteria #5 (limited to 10% of
randomized subjects)

- Hypertension as defined by systolic pressure =140 mmHg and/or diastolic pressure
=90 mmHg a) treated or untreated with systolic =140 mmHg or diastolic =90 mmHg or
b) treated with systolic <140 mmHg and diastolic <90 mmHg

- Dyslipidemia as defined by total cholesterol =200 or LDL =130 a) treated or
untreated with total cholesterol =200 or LDL =130 or b) treated with total
cholesterol <200 or LDL <130

- Sleep apnea syndrome (confirmed by overnight p02 studies)

- Obesity-related cardiomyopathy

3. Females or males Note: females of child-bearing potential must have a negative urine
pregnancy test at Screen and also within 14 days of implant procedure followed by
physician-approved contraceptive regimen for the duration of the study period.

4. 18-65 years of age inclusive.

5. Type 2 diabetes mellitus subjects:

- Glycosylated hemoglobin (HbA1c) 7.0 - 10.0 % inclusive at screening visit.
(Undiagnosed subjects that are found to have a HbA1c value between 7-10% at
screening must see their primary physician for diagnosis and medical treatment
before continuing in trial)

- Onset: 12 years or less since initial diagnosis.

- Currently not using insulin therapy, GLP-1 (glucagon-like peptide-1) receptor
agonists (e.g., exenatide, liraglutide) for diabetes treatment and have not been
on these treatments in the past 6 months.

- Creatinine within normal reference range.

- No history of proliferative retinopathy.

- No history of peripheral neuropathy.

- No history of autonomic neuropathy.

- No history of coronary artery disease, with or without angina pectoris.

- No history of peripheral vascular disease.

6. Failure to respond to supervised diet/exercise program(s) in which the subject was
engaged within the last five years.

7. Ability to complete all study visits and procedures.
Minimum age
18 Years
Maximum age
65 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Exclusion criteria

1. Concurrent chronic pancreatic disease.

2. History of Crohn's disease and/or ulcerative colitis.

3. History of bariatric surgery, fundoplication, gastric resection or major
upper-abdominal surgery (acceptable surgeries include cholecystectomy, hysterectomy).

4. History of pulmonary embolism or blood coagulation disorders.

5. Clinically significant hiatal hernias (> 5 cm) known from subject's medical record or
determined by barium swallow (upper GI x-ray) or upper endoscopy per PI discretion
prior to implant.

6. Current cirrhosis, portal hypertension and/or esophageal varices.

7. Intra-operative exclusion: hiatal hernia requiring surgical repair or extensive
dissection at esophagogastric junction at time of surgery.

8. Treatment with prescription weight-loss drug therapy within the prior three months and
the use of prescription drug therapy or the use of over-the-counter weight loss
preparations for the duration of the trial.

9. Smoking cessation within the prior six months.

10. Known genetic cause of obesity (e.g., Prader-Willi Syndrome).

11. Weight loss of more than 10% of body weight in the previous 12 months.

12. Physician-prescribed diet with intent to lose weight prior to surgery (note:

study subject may continue any personal eating plan they were on prior to study
enrollment [see exclusion criterion #24]

13. Current type 1 diabetes mellitus (DM).

14. Current or recent history (within 12 months) of ongoing bulimia.

15. Current alterations in treatment for thyroid disorders (stable treatment regimen for
prior three months acceptable).

16. Current alterations in treatment for epilepsy (stable treatment regimen for prior six
months acceptable).

17. Current treatment for peptic ulcer disease (previous history acceptable).

18. Chronic (more than 4 weeks of daily use) treatment with narcotic analgesic drug
regimens (treatment with non-steroidal anti-inflammatory drugs acceptable).

19. Current alterations in treatment regimens of anti-cholinergic drugs, including
tricyclic antidepressants (stable treatment regimen for prior six months acceptable).

20. Current medical condition that, in the opinion of the investigator, would make subject
unfit for surgery under general anesthesia or that would be exacerbated by intentional
weight loss. Some examples include diagnosis of cancer, recent heart attack, recent
stroke, or recent serious trauma.

21. Presence of permanently implanted electrical powered medical device or implanted
gastrointestinal device or prosthesis (e.g., pacemakers, implanted defibrillators,
neurostimulators etc.).

22. Planned or contemplated use of Magnetic Resonance Imaging (MRI) or oncologic radiation
during the course of the trial.

23. Psychiatric disorders (including untreated severe depression, schizophrenia, substance
abuse, bulimia nervosa, etc.) or limited intellectual functioning which would
potentially compromise the participant's ability to fully comprehend and/or cooperate
with the study protocol. Psychiatric disorders will be established by a review of
subject's medical history. For depression, a BDI (Beck Depression Inventory) score =
29 will be considered to indicate severe depression.

24. Current, active member of an organized weight loss program (e.g., Weight Watchers,

25. Current participant in another weight loss study or other clinical trials.

26. Have a friend or family member who is currently participating or is planning to
participate in this clinical trial.

27. Patient reported:

- inability to walk for about 10 minutes without stopping,

- feeling of pain in chest when doing physical activity,

- feeling of pain in chest when not doing physical activity. Note: unless pain in
chest in known to be related to upper gastrointestinal disorders such as
gastroesophageal reflux disease or heartburn.

28. Clinically significant cardiac rhythm disorder that requires either medical and/or
surgical intervention (e.g., paroxysmal or chronic atrial fibrillation).

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Unknown status
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 0 0
Institute of Weight Control - Baulkham Hills
Recruitment hospital [2] 0 0
Adelaide Bariatric Centre - Bedford Park, SA
Recruitment postcode(s) [1] 0 0
- Baulkham Hills
Recruitment postcode(s) [2] 0 0
- Bedford Park, SA
Recruitment outside Australia
Country [1] 0 0
United States of America
State/province [1] 0 0
Country [2] 0 0
United States of America
State/province [2] 0 0
Country [3] 0 0
United States of America
State/province [3] 0 0
Country [4] 0 0
United States of America
State/province [4] 0 0
Country [5] 0 0
United States of America
State/province [5] 0 0
Country [6] 0 0
United States of America
State/province [6] 0 0

Funding & Sponsors
Primary sponsor type
Commercial sector/Industry
ReShape Lifesciences

Ethics approval
Ethics application status

Brief summary
The study evaluated the safety and efficacy of the vBloc Therapy delivered by the Maestro
Rechargeable System compared to a sham control for the treatment obesity. The Maestro
Rechargeable System delivers intermittent, electrical blocking signals to the anterior and
posterior trunks of the intra-abdominal vagus nerve (termed vBloc Therapy) and is designed to
reduce sensations of hunger and produce satiety leading to weight loss. After approval from
the institutional review board, subjects provided written consent and were randomized in a 2
to 1 allocation to vBloc group (with laparoscopic placement of the leads and neuroregulator)
or the sham group (placement of a custom sham neuroregulator only) on double-blinded basis.
Both groups received similar diet and exercise counseling. Weight, adverse events, clinical
laboratories, ECGs, eating questionnaires and quality of life data were evaluated throughout
the 12 month study duration.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 0 0
Michael Sarr, M.D.
Address 0 0
Mayo Clinic
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for scientific queries

Summary results
For IPD and results data, please see