Endoluminal Barrier Promotes Weight Loss Without Surgery

Daniel M. Keller, PhD

May 18, 2012

May 18, 2012 (Lyon, France) — A different approach to bariatric treatment appears to be safe and effective in terms of weight loss and improvements in type 2 diabetes mellitus, and the entire procedure takes less than 30 minutes.

Jan Willem Greve, MD, PhD, from the Atrium Medical Center in Heerlen, the Netherlands, described an impermeable fluoropolymer duodenal-jejunal bypass liner, called the EndoBarrier, which keeps food from coming into contact with digestive enzymes and contacting the luminal surfaces in these areas. He presented findings from a study here at the 19th European Congress on Obesity.

EndoBarrier is a flexible, collapsible 60 cm tube with a large proximal opening that is delivered through the mouth using a preloaded single-use device. It is anchored with attached barbs that penetrate into the wall of the duodenum. After 1 year (the indicated use), it is removed the same way it was placed, leaving no incision scars.

The indications are similar to those for bariatric surgery, but the EndoBarrier might also be appropriate for people with a lower body mass index (BMI), who would not qualify for bariatric surgery.

Experience With EndoBarrier

In the study of 61 patients, the insertion time was 24.1 ± 11.21 minutes, and removal took 14.1 ± 24.03 minutes. Fluoroscopy time averaged 7.7 minutes for insertion and 1.6 minutes for removal.

Dr. Greve reported that there have been 13 studies of the device, involving more than 500 patients. In general, people with type 2 diabetes experienced immediate improvement in their condition, long-term improvement in their diabetes with weight loss, and delayed rebound of their diabetes after removal of the device. Many antidiabetic medications, including insulin, have the adverse effect of weight gain. Getting patients off those medications apparently enhances the weight loss induced by the device.

In a nonrandomized single-group study from Chile, the 27 patients who completed the study lost 47% of their excess weight. BMI fell from 45.3 kg/m² at baseline to 36.1 kg/m² at 12 months (P < .001). Blood pressure decreased from 134.0/85.7 mm Hg to 124.7/71.8 mm Hg (P = .003 for systolic; P < .001 for diastolic). There were statistically significant reductions in total cholesterol, low-density-lipoprotein cholesterol, and triglycerides, but high-density-lipoprotein cholesterol was unchanged.

A 1-year Brazilian study (n = 22) showed a beneficial effect on glycated hemoglobin (HbA1c). From a baseline average of 8.8% (range, 6% to 11.5%), HbA1c dropped to about 6.8% 12 weeks after the implantation of the EndoBarrier, and continued to drop to about 6.5% at 36 weeks, where it was at week 52 when the device was removed. Interestingly, HbA1c remained in that range for at least the next 24 weeks.

Dr. Greve said that the safety of the device looks very good. Common adverse events reported were nausea, vomiting, and abdominal pain. There was less than a 1% incidence of gastrointestinal (GI) hemorrhage, dehydration, constipation, diarrhea, hypoglycemia, and vitamin or mineral deficiencies.

"Apart from the migration of the anchor, you can have an obstruction of the sleeve; that has occurred in a number of patients," Dr. Greve said. Obstructions, which have occurred in about 3% of patients, can easily be cleared if they are caused by food boluses; however, a twist in the sleeve necessitates removal.

Increases in GI Hormone Secretion After EndoBarrier Implantation

In obese patients with type 2 diabetes, Dr. Greve's team saw rapidly improving parameters related to diabetes, paralleled by increased postprandial glucagon-like peptide (GLP)-1 and PYY, a GI protein that appears to reduce appetite. GLP-1 enhances glucose-dependent insulin secretion and suppresses postprandial glucagon secretion in the pancreas.

There was a rapid and sustained increase in insulin sensitivity. Blood glucose levels were lower after a feeding challenge at weeks 1, 24, and 25 than they were at day 0 (before implantation). The area under the curve (AUC) for blood glucose was 2000 mmol/L per min at day 0, and significantly reduced to 1500 mmol/L per min at weeks 1, 24, and 25.

There were increased blood concentrations, peak levels, and AUC for GLP-1 and for PYY at week 1, which diminished over time. Similarly, the glucagon response normalized at week 1 and continued to decrease to week 24, with significant differences in the glucagon AUC at both time points, compared with day 0 (P < .05).

Compared with day 0, at week 24, patients showed significant improvements in weight, excess weight, and HbA1c (P < .001 for all). Sixteen of 17 patients reduced their antidiabetic medications.

Dr. Greve concluded that the EndoBarrier is a "safe and effective procedure with significant results in patients with type 2 diabetes." He said he looks forward to improvements to the anchor, which limits how long the device can remain in the body. "It's really a pity that we haven't found the trick yet to have it stable for a longer period of time, because then it will be a really amazing treatment," he said.

Repeat placement is a possibility. "We know now that you need to have a certain lag time before you retreat, and then it...works just as well as the first time," he said.

Dr. Greve said the EndoBarrier endoluminal treatment is a good alternative to surgery and overcomes some of the risks inherent in any surgical procedure.

"What really surprised me is the patients; they are extremely pleased with the device because they hardly feel that it's there, but it helps them control their eating habit incredibly.... When it's in a good position, it gives so few side effects, and the patient is so happy," he explained.

Session chair Luca Busetto, MD, from the Department of Medical and Surgical Sciences and the Obesity Center at the University of Padova in Italy, who was not involved in the trial, told Medscape Medical News that the fact that the procedure is currently good for only 1 year is a problem, "but you need to remember that it is an endoscopic procedure, so we are not talking about a general surgery," he said. "This procedure, at least in theory, is easier to apply in larger numbers of patients."

He explained that earlier versions of the device could be used for 3 months and then 6 months. "Probably with some improvement in the technical aspects of the anchor...this time will become longer in the future," he predicted. Because the endoluminal sleeve is attached just below the pylorus, "the gastric emptying is reported to be quite normal," Dr. Busetto said.

Dr. Greve reports receiving a research grant from GI Dynamics, which produces the EndoBarrier; and receiving travel support from Johnson & Johnson, Covidien, and Allergan. Dr. Busetto has disclosed no relevant financial relationships.

19th European Congress on Obesity (ECO): Abstract 8. Presented May 10, 2012.


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