MetaCure has performed numerous clinical studies since 2003 in which over 200 patients have been implanted with the DIAMOND (TANTALUS) system. Between 2006 and 2010, several prospectively designed open label studies examined the effects of the DIAMOND System on glycemic control, changes in weight, and various metabolic factors in obese Type 2 Diabetic (T2DM) patients inadequately controlled by oral anti-diabetic agents.
The different studies conducted with the Diamond system worldwide demonstrate a consistent and significant reduction in HbA1c levels; in a per-protocol analysis, the mean decrease noted was as high as -1.0% (reduction of up to -3% observed). This effect was accompanied by a significant improvement in fasting blood glucose, blood pressure (systolic and diastolic), body weight mean reduction of -4.2kg (up to m-28kg) and other beneficial metabolic effects, suggesting a comprehensive effect of the Diamond System on diabetes and other co-morbidities associated with this disease. Following is a summary of some peer reviewed published articles:
Gastric Electrical Stimulation with the DIAMOND (TANTALUS) System in Obese Type 2 Diabetes Patients: Effect on Weight and Glycemic Control
Fourteen obese Type 2 Diabetes patients on oral antidiabetes medication and body mass index 39 ± 1 kg/m2, HbA1c 8.5 ± 0.2% were enrolled and implanted laparoscopically with the DIAMOND (TANTALUS) System. In the eleven subjects that reached the 6-month treatment period endpoint, HbA1c was reduced significantly from 8.5 ± 0.1% to 7.6 ± 1%, p < 0.01. Weight was also significantly reduced from 107.7 ± 21.1 to 102.4 ± 20.5 kg, p < .01. The improvement in glucose control did not correlate with weight loss (R2 = 0.05, p = .44). A significant improvement was noted in blood pressure, triglycerides, and cholesterol (low-density lipoprotein only).
Sanmiguel et al.,”Gastric electrical stimulation with the TANTALUS™ system in obese type 2 diabetics: effect on weight and glycemic control”, Journal of Diabetes Science and Technology, Volume 3, Issue 4: Page 964-970, July 2009.
Feasibility-Safety Study in Obese Type-2 Diabetes– a multi-center open-label study
Twenty-four obese Type 2 Diabetes patients previously treated with Insulin and/or oral hyperglycemic agents and body mass index between 33.3 to 49.7 kg/m2 were implanted laparoscopically with a DIAMOND (TANTALUS) system. In the 21 subjects that reached the 1-year visit HbA1c was reduced by 0.5±0.3% (p<0.05). In a subgroup (n=11) on stable or reduced oral medication (figure below), HbA1c was reduced by 0.9±0.4% (p<0.05). Improvements were observed in all the three dimensions of eating behavior. Cognitive control increased from 11.2±1.7 at baseline (week 0) to 14.0±1.2 (week 20, p<0.05) and remained at that level by week 52 reaching 13.7±1.3 (p<0.05).
Figure: Effect in body weight and glycemic control on oral subjects. A subgroup of patients on stable oral medication and basal HbA1c between 7.5% and 9.5% exhibited comparatively more improvement in weight (blue) and glycemic control (orange, upper panel). *p<0.05 compared to baseline. Correlation between changes in body weight and HbA1c (lower panel) show a greater effect of weight on HbA1c changes.
Electrical Stimulation of the Gut for the Treatment of Type 2 Diabetes: The Role of Automatic Eating Detection
Twelve obese patients were implanted with gastric leads and the DIAMOND
(TANTALUS) device. An Automatic Eating Detection
(AED) algorithm was embedded in the device and was used to initiate periods of electrical stimulation during food intake. The algorithm was able to detect 73% of meals consumed while sensing. The rate of false stimulations was 28%. Stimulation during meals was significantly correlated (R2 = 0.45, p < 0.05) with HbA1c change (average drop in HbA1c was –1 ± 0.4%)
but not with changes in body weight (average drop –4.7 ± 2.8 kg).
Figure: Values of HbA1c changes and the corresponding rate of stimulated meals per patient.
Policker et al., “Electrical Stimulation of the Gut for the Treatment of Type 2 Diabetes: The Role of Automatic Eating Detection”, Journal of Diabetes Science and Technology Volume 2, Issue 5, September 2008.
First Feasibility-Safety Study in Morbid-Obese – a prospective, non-randomized, open-label study
Twelve patients with BMI 35-50 kg/m2 and a history of at least 5 years of obesity underwent laparoscopic implantation with the Tantalus™ (previous generation to the DIAMOND) system. The system was activated at week 6. All subjects were followed for 20 weeks and 9 of them for 52 weeks. Following activation of the system, a reduction (P<0.05) in hunger and an increase in cognitive control (P<0.05) as assessed by the Three-Factor Eating Questionnaire (TFEQ) could be observed. Body weight decreased (P<0.05) from 128.8±5.2 to 119.9+5.9 (17.6+4.3% EWL, N=12) after 20 weeks (14 weeks of treatment). In the 9 subjects continuing for 52 weeks (46 weeks of treatment), body weight further decreased to 112.4 ± 3.8 kg (26.6 ± 8.5 %EWL, N=9). Blood pressure decreased (P<0.05) from 142 ± 6.1/91 ± 3.2 to 125.5 ± 4.0/83 ± 2.6 mmHg by week 20 and 128.8 ± 3.8 / 86.3 ± 3.6 mmHg after 1 year. The frequency and severity of device and/or procedure-related adverse events indicate that the method is safe and well-tolerated.
Figure: Excess weight loss relative to baseline with the DIAMOND system. Weight loss distributed by response on group A (n=9; circles) and group B (n=3; squares). Three subjects dropped out of the study on week 20 (n=2) and on week 28 (n=1).
Bohdjalian A et al “One-Year Experience with TANTALUS™: a New Surgical Approach to Treat Morbid Obesity” Obesity Surgery, 2006; (16): 627-634.
At present, several randomized/ comparative clinical studies are being conducted in Europe and Asia. These studies will establish the proper positioning of the DIAMOND system in the treatment continuum of T2DM.