Early Feasibility of Endoscopic Gastric Mucosal Ablation (GMA) as a Primary Obesity Therapy


About this study

The purpose of this study is to assess the feasibility of ablation of up to 70% of the gastric mucosa using HybridAPC to induce weight loss.  

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

1. Male or females patients in the range of class I to class III obesity (BMI ≥ 30 to ≤
40 with obesity-related comorbidity or BMI > 40 to BMI ≤ 45).

2. Age 22 - 60 yrs.

3. Treatment naïve for bariatric surgery or endoscopic bariatric therapy

4. Agree to avoid any use of weight loss medications such as Meridia, Saxenda, Januvia,
Xenical, Duromine or over the counter weight loss medications or supplements
throughout the study.

5. Women of childbearing potential (WOCBP) must agree to use acceptable contraception

6. Agree not to donate blood during their participation in the study.

7. Able to comply with study requirements and understand and sign the Informed Consent

8. Stable weight defined as a fluctuation of less than 5% for at least 3 months prior to
screening visit.

9. History of failure to lose weight using conventional diet and lifestyle therapies.

Exclusion Criteria:

1. Patients requiring exogenous insulin.

2. HbA1c > 8.5 %

3. Pregnant or breast-feeding or intending to get pregnant during the study.

4. Unwilling or unable to complete the Visual Analogue Scale for pain assessment, patient
questionnaires, or comply with study visits and other study procedures as required per

5. History of diabetic ketoacidosis or hyperosmolar nonketotic coma.

6. Probable insulin production failure, defined as fasting C-Peptide serum < 1 ng/mL (333

7. Previous use of any types of insulin for > 1 month (at any time, except for treatment
of gestational diabetes).

8. Change in diabetic treatment within the last three months.

9. Use of glucose-lowering drugs for diabetes mellitus treatment with the exception of
sulfonylurea (SU), biguanides and sodium dependent glucose co-transporter 2 (SGLT-2)

10. Change of diabetes medication or doses 12 weeks prior to screening visit.

11. Hypoglycemia unawareness or a history of severe hypoglycemia (more than 1 severe
hypoglycemic event, as defined by need for third-party-assistance, in the last year).

12. Known autoimmune disease, including but not limited to celiac disease, or pre-existing
symptoms of systemic lupus erythematosus, scleroderma or other autoimmune connective
tissue disorder.

13. Previous upper GI surgery, or other endoscopic bariatric procedures or conditions,
prior intra-gastric balloon or another gastric implant.

14. History of diabetic gastroparesis.

15. Known active hepatitis or active liver disease.

16. Acute gastrointestinal illness in the previous 7 days.

17. Known history irritable bowel syndrome, radiation enteritis or other inflammatory
bowel disease, such as Crohn's disease.

18. Known history of a structural or functional disorder of the esophagus that may impede
passage of the device through the gastrointestinal tract or increase risk of
esophageal damage during an endoscopic procedure, including Barrett's esophagus,
esophagitis, dysphagia, achalasia, stricture/stenosis, esophageal varices, esophageal
diverticula, esophageal perforation, or any other disorder of the esophagus.

19. Known history of a structural or functional disorder of the esophagus, including any
swallowing disorder, esophageal chest pain disorders, or drug refractory esophageal
reflux symptoms.

20. Known history of a structural or functional disorder of the stomach including
gastroparesis, gastric ulcer, chronic gastritis, gastric varices, hiatal hernia (>3
cm), cancer or any other disorder of the stomach.

21. Known history of chronic symptoms suggestive of a structural or functional disorder of
the stomach, including any symptoms of chronic upper abdominal pain, chronic nausea,
chronic vomiting, chronic dyspepsia or symptoms suggestive of gastroparesis, including
post-prandial fullness or pain, post-prandial nausea or vomiting or early satiety.

22. Currently have ongoing symptoms suggestive of intermittent small bowel obstruction,
such as recurrent bouts of post-prandial abdominal pain, nausea or vomiting.

23. Active H. pylori infection (Subjects with active H. pylori may continue with the
screening process if they are treated with an appropriate antibiotic regimen, and
eradication has been confirmed).

24. History of coagulopathy, upper gastrointestinal bleeding conditions such as ulcers,
gastric varices, strictures, congenital or acquired intestinal telangiectasia.

25. Current use of anticoagulation therapy

26. Obligate use of anti-inflammatory drugs that cannot be suspended for a minimum of 4
weeks post procedure

27. Use of systemic glucocorticoids (excluding topical or ophthalmic application or
inhaled forms) for more than 10 consecutive days within 90 days prior to the Screening

28. Use of drugs known to affect GI motility (e.g. Metoclopramide).

29. Receiving any weight loss medications such as Meridia, Xenical, Saxenda, Januvia,
Duromine or over the counter weight loss medications at screening.

30. Untreated/inadequately treated hypothyroidism, defined as an elevated
Thyroid-Stimulating Hormone (TSH) level at Screening; if on thyroid hormone
replacement therapy, must be on stable dose for at least 6 weeks prior to Screening.

31. Persistent Anemia, defined as Hemoglobin <10 g/dL.

32. Significant cardiovascular disease including known history of valvular disease, or
myocardial infarction, heart failure, transient ischemic attack or stroke within the
last 6 months.

33. Known moderate or severe chronic kidney disease (CKD), with estimated glomerular
filtration rate (eGFR) <45 ml/min/1.73m2 (estimated by MDRD).

34. Known immunocompromised status, including but not limited to individuals who have
undergone organ transplantation, chemotherapy or radiotherapy within the past 12
months, who have clinically-significant leukopenia, who are positive for the human
immunodeficiency virus (HIV) or whose immune status makes the subject a poor candidate
for clinical trial participation in the opinion of the Investigator.

35. Active systemic infection.

36. Known active malignancy within the last 5 years (with the exception of treated basal
cell or treated squamous cell carcinoma).

37. Subjects with an established diagnosis of Multiple Endocrine Neoplasia syndrome type

38. Not a candidate for surgery or general anesthesia.

39. Active illicit substance abuse or alcoholism.

40. Current smoker or smoking history in the last six months.

41. Participating in another ongoing clinical trial of an investigational drug or device.

42. Any other mental or physical condition which, in the opinion of the investigator,
makes the subject a poor candidate for clinical trial participation.

43. Other medical condition that does not allow for endoscopic procedure.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Eligibility last updated 6/20/23. Questions regarding updates should be directed to the study team contact.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Jacksonville, Fla.

Mayo Clinic principal investigator

Dilhana Badurdeen, M.B.B.S., M.D.

Open for enrollment

Contact information:

Clinical Studies Unit

(904) 953-2255

More information


  • As the pig model has similar gastrointestinal anatomy and physiology to humans, we used pigs to create a gastric mucosal devitalization (GMD) model in preparation for clinical translation of this technique as an endoscopic bariatric therapy (EBT). The aims of this study were to determine the ablation parameters and technique for a successful, safe, and feasible large surface area GMD that produces weight loss. Read More on PubMed
  •  In lieu of the drawbacks of metabolic surgery, a method of mimicking resection of the gastric mucosa could be of value to those with obesity-related cardiovascular disease (CVD). Our study aims to investigate the effect of gastric mucosal devitalization (GMD) on blood pressure (BP) and cardiovascular lipid deposition in a rat model of obesity.  GMD of 70 % of the stomach was achieved by argon plasma coagulation. GMD was compared to sleeve gastrectomy (SG) and sham (SH) in a high-fat-diet-induced rat model of obesity (48 rats). At 8 weeks, we measured noninvasive BP, renin, vessel relaxation and ghrelin receptor regulation in the aorta. In addition, we quantified cardiac lipid deposition and lipid droplet deposition in cardiac muscle and aorta.  GMD and SG were observed to have similar reductions in body weight, visceral adiposity, and serum lipid profile compared to SH rats. GMD resulted in a significant reduction in arterial BP compared to SH. Furthermore, there were significant reductions in plasma renin activity and percentage of phenylnephrine constriction to acetylcholine at the aortic ring in GMD rats compared to SH, providing insights into the mechanisms behind the reduced BP. Interestingly, the reduced BP occurred despite a reduction in endothelial ghrelin recteptor activation. Cardiac lipid content was significantly reduced in GMD rats. Lipid deposition, as illustrated by Nile Red stain, was reduced in cardiac muscle and the aorta.  GMD resulted in a significant improvement in BP, renin and cardiovascular lipid deposition. GMD deserves further attention as a method of treating obesity-related CVD. Read More on PubMed
  •  The metabolic effects of bariatric surgery may partially result from removal of the gastric mucosa, an often underappreciated endocrine organ. Using argon plasma coagulation (APC), we may be able to selectively devitalize (ablate) the mucosa. The aim of this study was to identify the optimal tissue color that would correspond to selective gastric mucosal devitalization (GMD) using ex-vivo human stomach specimens.  Stomach specimens were obtained at sleeve gastrectomy. Prior to APC application, a submucosal fluid cushion was created. APC was then applied over a 2 × 2-cm area to the fundus and body, aiming for the three indicator colors (white, golden, brown). Pathological analysis was then performed independently and in a blinded fashion by two pathologists to determine the depth of mucosal and submucosal percent thermal injury and mucosal percent cell death.  Six patients were enrolled. There was a significant correlation between tissue color and mucosal percent thermal injury. The highest percent mucosal thermal injury was seen with brown (99.6 %, 95 % CI: 98.7, 100), followed by golden (92.5 %, 95 % CI: 85.5, 99.5), and then white (75.2 %, 95 % CI: 58.3, 92.1,  < 0.01). Submucosal thermal injury was seen in 88.9 % of the slides. Greater than minimal submucosal injury (> 10 % depth) was found significantly more with brown tissue color (91.6 %) than golden (75 %) or white (33.3 %,  < 0.05). However, 91.7 % of the entire sample set < 50 % injury.  GMD is achievable using APC without thermal injury to muscularis propria. A golden color results in sufficient mucosal injury with only superficial injury to the submucosa. Read More on PubMed
  • The early improvement in metabolic profile after sleeve gastrectomy (SG) indicates that the significant benefits of metabolic surgery are gastric in origin. We have previously demonstrated that devitalization of the gastric mucosa (without a reduction in gastric volume) in metabolically disturbed obese rats results in an improvement of obesity and its associated comorbidities. The aims of this study were to assess the technical feasibility, efficacy, and safety of gastric mucosal devitalization (GMD) in a large animal (porcine) model. Read More on PubMed
  • The gastric mucosa is an endocrine organ that regulates satiation pathways by expression of orexigenic and anorexigenic hormones. Vertical sleeve gastrectomy (VSG) excludes gastric mucosa and reduces gastric volume. Our study aimed to investigate the independent effects of altering gastric mucosa on obesity and its related comorbidities. Read More on PubMed

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