A One-Time Intervention for Type 2 Diabetes

DIAMOND system

Fully Reversible, Minimally Invasive Treatment for T2D

Implantable Pulse Generator

The small pulse generator is implanted subcutaneously in the upper left abdomen and delivers meal-mediated gastric contractility modulation (GCM) pulses through two electrodes attached to the posterior and anterior of the gastric antrum subserosal layer. A third lead connected to the subserosal layer of the gastric fundus is used to detect when food has entered the stomach. The minimally invasive implantation procedure is performed laparoscopically, with no changes to the anatomy, and is fully reversible. The device can be used for up to 15 years1 before a replacement is needed.

The DIAMOND (Tantalus) System is CE marked and available for commercial use. The DIAMOND II System is not CE marked currently.

Patient Charger

The external wireless charger is placed over the abdomen for 45 minutes each week to recharge the implantable pulse generator. This can be performed by the patient at home.

Physician Tablet

The programmer is used by certified physicians or clinical technicians to set and control the therapy parameters for DIAMOND through wireless connectivity.

Image used for illustrative purposes only, actual model may vary.


DIAMOND has received CE mark and is approved for sale in Europe, Australia and other international markets.  DIAMOND is not approved for use in the USA.

Mechanism of action

Activation of the Gut-Brain-Liver Axis

When food enters the stomach of a healthy individual signals are transmitted along the vagus nerve to the hypothalamus. The hypothalamus then alerts the liver and pancreas to prepare for a change in energy (glucose) concentration. In response, the liver lowers glucose production and the pancreas releases insulin and decreases glucagon production. This gut-brain-liver axis is impaired in T2D,1 which can lead to a 30- to 45-minute delay in signals to the liver and pancreas and subsequent high post-prandial glycemia.

Gastric Contractility Modulation normalizes the timing of signals from the gut and accelerates satiation. Non-excitatory energy (GCM*) is transmitted from a pulse generator to electrodes attached to the antrum of the stomach when food is consumed. The gentle stimulation immediately increases antral muscle contraction force to the level that is reached when the stomach is distended with food.2 Mechanoreceptors detect this contraction and activate the gut-brain-liver axis by sending a signal through the vagus nerve to the hypothalamus, restoring the physiological synchronization between food intake and natural hormone secretion.3  This process also activates satiety centers, causing the patient to feel full sooner.4

* Gastric contractility modulation (GCM) is non-excitatory stimulation of the gastric antrum.  Unlike common tissue stimulation (e.g. cardiac pacemakers) GCM signals are non-excitatory since they are applied during the absolute refractory period of the muscle cells’ contraction cycle.  GCM signals have been shown to significantly increase antral muscles contraction force.5

Clinical evidence

Over 300 patients have been treated in clinical studies.6
Clinical trials have demonstrated that gastric contractility modulation using DIAMOND significantly reduces HbA1c. When stimulation is not used, HbA1c returns to elevated levels.7 In a controlled, case-paired trial, DIAMOND was shown to be as effective as insulin in lowering HbA1c at one year yet, contrary to insulin, caused weight loss and reduced blood pressure levels.8


Sustained decrease in HbA1c
At three-year follow up, HbA1c decreases averaged 0.9% for obese patients refractory to oral T2D medication treated with DIAMOND. There was higher HbA1c reduction of 1.1%, on average, for patients with normal triglyceride levels.11 Other studies evaluating DIAMOND in similar patient populations have also demonstrated significant reduction in HbA1c.12,13,14

Long-Term Response of T2D Patients with Normal Triglycerides Treated with DIAMOND9

Average HbA1c level of treated patients over three years (cross-sectional and longitudinal data). The decrease in HbA1c in these patients was durable over the three years and averaged at 1.1% (ANCOVA p=0.001). Reproduced from Lebovitz HE et al. Hormone and Metabolic Research, 2015.10

DIAMOND was Equally Effective as Insulin While Avoiding Most Side Effects16

Changes from baseline in a 12-month study comparing DIAMOND against insulin therapy for diabetes in obese type 2 diabetes patients. The two therapies generated a comparable drop in HbA1c levels. However, body weight, body fat, waist circumference and mean 24h systolic BP tended to decrease under DIAMOND therapy, as opposed to an increasing trend exhibited under insulin therapy. Produced from data by Wong SK, Kong AP, Luk AO, et al. A pilot study to compare meal-triggered gastric electrical stimulation and insulin treatment in Chinese obese type 2 diabetes. Diabetes Technol Ther. 2015;17(4):283-90.

Weight loss
By generating an early satiation effect15, DIAMOND therapy also results in weight loss of around 5kg. For patients with normal triglycerides, weight loss of approximately 10% of total body weight can be achieved and sustained. Over half the patients experience weight loss of over 10%16 and some patients also experience a reduction in waist circumference.17

Sustained Weight Loss

Changes in body weight as percentage from baseline in obese type 2 diabetes patients with low triglyceride level over 12, 24 and 36 months under DIAMOND therapy. Produced from data published in Lebovitz HE, Ludvik B, Yaniv I, et al. Treatment of Patients with Obese Type 2 Diabetes with Tantalus-DIAMOND® Gastric Electrical Stimulation: Normal Triglycerides Predict Durable Effects for at Least 3 Years. Horm Metab Res. 2015;47(6):456-62. Significant decrease in weight under DIAMOND therapy was also demonstrated in several other studies.

Lower systolic blood pressure
DIAMOND has been shown to significantly and durably reduce systolic blood pressure by approximately 10 mmHg-15 mmHg18 and may enable a reduction in hypertension medication.19

Open-Label Study of DIAMOND in T2D Patients6

81 patients with type 2 diabetes and inadequately controlled with oral antidiabetic agents were treated with DIAMOND therapy.  Patients were not restricted to a certain diet or exercise regime.  HbA1c level and weight are shown at baseline and six months into the therapy (p<0.01). Presented by Prof. Lebovitz HE at the IDF Congress, Melbourne 2013.


Implantation of DIAMOND has risks similar to other surgical laparoscopic procedures.21 DIAMOND therapy is well tolerated by patients and has minimal side effects.22

Advantages of DIAMOND

Current solutions – Unwanted side effects and adherence problems

Longstanding T2D treatments can result in hypoglycemia, weight gain, or other unwanted side effects.23 Over 70% of patients report experiencing side effects, and difficulty tolerating T2D medications has been shown to lower adherence.24

As T2D progresses, treatment typically needs to be intensified to achieve target HbA1c goals. Newer oral T2D therapies, often used as an add-on treatment to metformin, have moderate efficacy in lowering HbA1c levels.25 In addition, multi-drug regimens can be challenging for patients to follow and further jeopardize adherence.

Many patients with T2D do not want an injectable treatment, such as insulin, because of inconvenience (frequent finger sticks and injections) or fear of hypoglycemia, weight gain and other side effects. Insulin can lead to hypoglycemia, which is associated with severe consequences.26 Overweight or obese patients find additional weight gain, which is a common side effect of insulin, particularly problematic. Furthermore, initiating insulin often consumes significant healthcare resources for patient education and management.

DIAMOND – Performance without compromise

Many patients with T2D will eventually require treatment escalation from oral medication to achieve HbA1c targets. Compared to oral T2D therapies, DIAMOND could offer superior glycemic reduction, with the additional benefits of weight reduction and lower systolic blood pressure. DIAMOND may be a preferable option compared to treatment escalation with insulin, which requires frequent monitoring and is associated with hypoglycemia and weight gain.

This table was developed based on information in the American Diabetes Association’s Standards of Medical Care in Diabetes–201527 and clinical data on DIAMOND therapy.28

DIAMOND procedural benefits – A minimally invasive, reversible solution

Interventional treatments for diabetes are increasingly accepted for obese patients who require treatment escalation. Unlike other procedures, implantation of the DIAMOND does not change anatomy and is fully reversible. Additionally, unlike bariatric surgery, DIAMOND therapy does not result in gastrointestinal side effects or strict dietary constraints. Finally, fast recovery from the implantation procedure allows patients to be discharged from the hospital within 24 – 48 hours after the procedure31.

Treating T2D with DIAMOND

Who should be considered for DIAMOND?

DIAMOND is a one-time intervention treatment for patients with type 2 diabetes who are obese and refractory to oral medication. Clinical trials have demonstrated durable glucose control and weight loss, with minimal side effects. Accordingly, DIAMOND could be a preferred treatment option for patients who are otherwise considered for injectable therapies.

Typical patient profile for DIAMOND therapy

  • T2D refractory to oral medication
  • BMI of 30-40
  • Elevated HbA1c
  • Normal blood triglycerides levels

Download the patient profile checklist

Implantation procedure

The minimally invasive laparoscopic DIAMOND implantation procedure lasts around 90 minutes and is performed under general anesthesia.

First, three bi-polar leads (each bifurcating to two electrodes) are introduced and attached to the stomach. One lead is attached to the subserosal layer of the fundus, for recording of the fundus distension. The remaining two leads are attached to subserosal layer of the posterior and anterior stomach walls for detecting slow-waves and delivery of gastric contractility modulation (GCM) signals.

The DIAMOND implantable pulse generator (IPG) is then connected to the leads and placed in a subcutaneous pocket in the abdomen. The connectivity of the system and the charging functions are tested before wound closure.

Post implantation, the patient receives standard post-operative care typically for 24 to 48 hours prior to discharge from the hospital.

The DIAMOND therapy poses a low rate of complications consistent with similar laparoscopic procedures. The most common adverse side effect is transient post-operative pain.


DIAMOND therapy is typically activated one week after the procedure as part of a routine post-procedure check-up and suture removal. The parameters for optimal food detection and gastric contractility modulation (GCM) signals are tested and configured individually for each patient using the wireless physician tablet. It is recommended to carry out an additional device check-up a week later. Annual device check-ups are recommended thereafter.

Image used for illustrative purposes only, actual model may vary.

Living with DIAMOND

Patients receiving DIAMOND therapy are not limited in their diet and can lead an active lifestyle.* Maintaining a healthy and balanced diet will contribute to the success of the treatment.

The device is fully automated and activation by the patient is not required. Weekly charging of the device lasts about 45 minutes and is easily carried out with the non-invasive patient wireless mobile charger device. As a result, patient compliance is very high. In case of a device malfunction, the charger device alerts the patient to contact his physician for further information.

* Not including contact sports or activities that could damage the implanted system.

Centers of excellence

A growing network of centers offer the DIAMOND therapy.

The DIAMOND network is growing all the time. Centers offering DIAMOND are shown below. If you are interested in DIAMOND therapy but cannot find a nearby center, or if you would like to offer DIAMOND therapy at your center, please contact us at centers@MetaCure.com

General and GI Tract Surgery Dept and Dept of Endocrinology, Centre for Postgraduate Medical Education (CMKP) Warsaw

Ul. Cegłowska 80, 01-001 Warszawa, Poland

General and GI Tract Surgery Dept and Dept of Endocrinology, Centre for Postgraduate Medical Education (CMKP) Warsaw

Ul. Czerniakowska 231, 00-416 Warszawa, Poland

TianTan Hospital , Capital Medical University, Beijing

Tian Tan Yi Yuan Kou, Dongcheng Qu, Beijing Shi, China, 100050

Peking University Diabetes Center, Beijing

Peking University People’s Hospital, No.11 Xizhimen South Street, Xicheng District, Beijing,100044,P. R. China

CHU Dijon, Hôpital de Bocage, Dijon

Bd Maréchal de Lattre de Tassigny, 21000 Dijon, France

Centre Hospitalier Universitaire de Nancy, Brabois Hospital, Nancy

Rue Morvan, 54511 Vandoeuvre- les-Nancy, France

CHRU Montpellier, Service des Maladies Endocriniennes, Montpellier

371 avenue du Doyen Gaston Giraud, 34295 Montpellier, France

Department of Surgery, CUHK, Prince of Wales Hospital, Hong Kong

Ngan Shing Street 1, Shatin, Hong Kong

Atrium MC

Henri Dunantstraat 5 6401 Heerlen, The Netherlands

Emovis GmbH, Bereich Klinische Forschung, Berlin

Wilmersdorfer Straße 79, 10629 Berlin, Germany

Diabetes-Praxis, Muenster

Düesbergweg 128, 48153 Münster, Germany

Krankenhaus Sachsenhausen, Fachbereich Diabetologie und Endokrinologie, Frankfurt am Main

Schulstraße 31, 60594 Frankfurt am Main, Germany

Asklepios Klinik St. Georg, Hamburg

Lohmühlenstraße 5, 20099 Hamburg, Germany

Universitätsklinikum Carl Gustav Carus, Technischen Universität , Dresden

Fetscherstraße 74, 01307 Dresden, Germany

Epworth Research Institute, Endocrinology Department, Richmond, Victoria

185-187 Hoddle Street, Richmond, Victoria, Australia, 3121

Azienda Ospedaliera Universitaria San Martino, Genova

Largo Rosanna Benzi 8, 16132 Genova, Italy

Università Cattolica del Sacro Cuore, Policlinico A. Gemelli , Rome

Istituto di Medicina Interna, Largo Agostino Gemelli 8, 00168 Roma, Italy

Institut za Pluće Bolesti Vojvodine, Klinika za Grudnu Hirurgiju, Novi Sad

Put doktora Goldmana 4., 21204 Sremska Kamenica, Serbia

Klinički Centar Srbije, Klinika za Digestivnu Hirurgiju, Belgrad

Koste Todorovića 6., 11000 Belgrade, Serbia

Allgemeines Krankenhaus (AKH), Wien

Universitätsklinik für Chirurgie, Klinische Abteilung für Allgemeinchirurgie Klinische Abteilung für Endokrinologie und Stoffwechsel, A-1090 Wien, Austria

“Evgenidio “ Hospital, Unit of Endocrinology, Metablism and Diabetes, Athens

Alkmanos 18, Postal Code: 11528, Athens, Greece

Dept. of General and Minimally Invasive Surgery, Faculty of Medicine, Warmia and Mazury University, Olsztyn

Ul.Niepodległości 44, 10-045 Olsztyn, Poland

Endocrinology, Dabetology and Internal Disease Dept., Medical University of Bialystok

Ul. Marii Skłodowskiej-Curie 24A, 15-276 Białystok, Poland

Centre for Diabetes and Obesity Treatment „DIABETA-CARE” of Lubin

Ul. Sztygarska 30, 59-300 Lubin, Poland

Endocrinology and Diabetology Dept, Medical University of Bydgoszcz

Ul. M. Skłodowskiej-Curie 9, 85-094 Bydgoszcz, Poland

Endocrinology and Internal Disease Dept. Pomeranian Medical University of Szczecin

Ul.Unii Lubelskiej 1, 71-252 Szczecin, Poland

The Netherlands

Atrium MC

[1] Based on MetaCure’s estimate.
[2] Burcelin R. The gut-brain axis: A major glucoregulatory player. Diabetes Metab. 2010;36 Suppl 3:S54-8.
[3] Policker S, Haddad W, Yaniv I. Treatment of type 2 diabetes using meal-triggered gastric contractility modulation. IMAJ. 2009;11:206-208.
[4] Lebovitz HE, Yaniv I, Schwartz T, Zelewski M, et al. Treatment of patients with obese type 2 diabetes with Tantalus-DIAMOND® gastric contractility modulation: Normal tryiglycerides predict durable effect for at least 3 years. Horm Metab Res. 2015;47:456-62.
[5] Ibid.
[6] Lebovitz H. Gastric Contractility Modulation in the Management of Type 2 Diabetes. Diabetes Management. Touch Briefings. 2007; 39-41.
[7] As of August 2015; data on file.
[8] Lebovitz HE, Ludvik B, Kozakowski J, Tarnowski W, et al. Gastric electrical stimulation treatment of type 2 diabetes: Effects of implantation versus meal-mediated stimulation. A randomized blinded cross-over trial. Physiol Rep. 2015;3: pii: e12456.
[9] Wong SK, Kong AP, Luk AO, Ozaki R, et al. A pilot study to compare meal-triggered gastric contractility modulation and insulin treatment in Chinese obese type 2 diabetes. Diabetes Technol Ther. 2015;17:283-90.
[10] Lebovitz HE, Yaniv I, et al, 2015.
[11] Ibid.
[12] Lebovitz HE, Yaniv I, et al, 2015.
[13] Sanmiguel CP, Conklin JL, Cunneen SA, Barnett P, et al. Gastric electrical stimulation with the TANTALUS® system in obese type 2 diabetes patients: Effect on weight and glycemic control. J Diabetes Sci Technol. 2009;3:964-70.
[14] Bohdjalian A, Prager G, Rosak C, Weiner R, et al. Improvement in glycemic control in morbidly obese type 2 diabetic subjects by gastric stimulation. Obes Surg. 2009;19:1221-1227.
[15] Lebovitz HE, Ludvik B, Yaniv I, Haddad W, et al. Fasting plasma triglycerides predict the glycaemic response to treatment of type 2 diabetes by gastric stimulation. A novel lipotoxicity paragram. Diabet Med. 2013;30:687-93.
[16] Wong SK, Kong AP, Luk AO, Ozaki R, et al. A pilot study to compare meal-triggered gastric contractility modulation and insulin treatment in Chinese obese type 2 diabetes. Diabetes Technol Ther. 2015;17:283-90.
[17] Ibid. Lebovitz HE, Yaniv I, et al, 2015.
[18] Ibid.
[19] Wong SK, et al, 2015.
[20] Lebovitz HE, Yaniv I, et al, 2015; Sanmiguel CP, et al, 2009.
[21] Wong SK, et al, 2015.
[22] Lebovitz HE. “Gastric electrical stimulation (GES) in T@2DM improves long-term glycemic control through a triglyceride-dependent mechanism.” Presented at the International Diabetes Federation conference. December 3, 2013. Melbourne, Austrialia.
[23] Policker S, et al, 2008; Bohdjalian A, et al, 2009.
[24] Ibid.
[25] Handelsman Y, Bloomgarden ZT, Grunberger G, Umpierrez G, et al. American Association of Clinical Endocrinologists and American College of Endocrinology – Clinical practice guidelines for developing a diabetes mellitus comprehensive care plan –2015. Endocr Pract. 2015;21 Suppl 1:1-487
[26] Pollack MF, Purayidathil FW, Bolge SC, Williams SA. Patient-reported tolerability issues with oral antidiabetic agents: Associations with adherence; treatment satisfaction and health-related quality of life. Diabetes Res Clin Pract. 2010;87:204-10.
[27] American Diabetes Association (ADA). Standards of care in diabetes—2015. Diabetes Care. 2015;38 Suppl:S4.
[28] Hanefeld M, Duetting E, Bramlage P. Cardiac implications of hypoglycaemia in patients with diabetes – A systematic review. Cardiovasc Diabetol. 2013;12:135.
[29] ADA, 2015.
[30] Lebovitz HE, Yaniv I, et al, 2015; Sanmiguel CP, et al, 2009; Policker S, et al, 2008; Bohdjalian A, et al, 2009.
[31] Sanmiguel CP, et al, 2009.