Perspective from Martin Binks, PhD, FTOS
January 14, 2015
3 min read

FDA approves VBLOC Maestro Rechargeable System to treat obesity

Perspective from Martin Binks, PhD, FTOS
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The FDA today approved the VBLOC vagal nerve blocking therapy, delivered via the Maestro Rechargeable System, to treat obesity by targeting the nerve pathway between the brain and stomach to regulate feelings of hunger and fullness, according to a press release from the agency.

The first obesity device to gain FDA approval since 2007 and the only that works based on this mechanism, VBLOC and Maestro (EnteroMedics) are approved for patients aged ≥18 years with BMI from 40 and 45, or BMI from 35 to 39.9 with at least one obesity-related condition, who have not achieved weight loss with a program.

“By blocking signals along the nerves that connect the brain and stomach, VBLOC reduces feelings of hunger and promotes earlier feelings of fullness, which can help people with obesity reduce the number of calories consumed and promote safe, healthy and durable weight loss,” Scott Shikora, MD, FACS, chief consulting medical officer for EnteroMedics said in a release from the company. 

Maestro is made up of rechargeable electrical pulse generator, wire leads and electrodes surgically implanted into a patient’s abdomen, according to the FDA release. Intermittent electrical pulses get sent to the trunks in the abdominal vagus nerve, which helps to regulate stomach emptying and signal the brain on feelings of emptiness or fullness.

Caroline Apovian

Carline M. Apovian

It is understood that the electric stimulation blocks nerve activity between the brain and the stomach, but the specific mechanisms by which the device helps patients lose weight are unknown, according to the release.

The device is charged by patients through external controllers, by which health care professionals can also adjust the settings to provide optimal therapy with minimal side effects.

Maestro was found to be safe and effective in a clinical trial involving 233 patients with BMI ≥35. Investigators compared weight loss and adverse events in 157 patients who received an active Maestro device and 76 who received an inactive pulse generator; at 12 months, patients lost 8.5% more excess weight with Maestro vs. the control group.

In the Maestro group, 52.5% of patients lost ≥20% excess weight, and 38.3% lost ≥25%. However, the study did not meet its original endpoint for at least half the Maestro group to lose at least 10% more excess weight than the control group.

An FDA advisory committee found 18-month data supported sustained weight loss and approved the devise based on benefits outweighing risks in patients meeting criteria in the proposed indication, according to the release. The clinical study, panel recommendations and FDA-sponsored survey on device-related risks were considered.

The manufacturer is required to conduct a 5-year post-approval study that will follow ≥100 patients and collect more safety and efficacy data on weight loss, adverse events, surgical revisions and explants and changes in obesity-related conditions.

EnteroMedics anticipates that the device will be available, on a limited basis, at select Bariatric Centers of Excellence in the US this year, according to the release from the company.

More than one-third of all adults in the US have obesity, according to the CDC, and therefore at increased risk for cardiovascular disease, stroke, type 2 diabetes and certain cancers.

“From diet and exercise to bypass surgery, existing treatment options have failed to stop the advance of this disease,” Caroline M. Apovian, MD, FACP, FACN, of Boston University School of Medicine, and director of Nutrition and Weight Management at Boston Medical Center, said in a release from the company. “The Maestro System adds a safe and effective new weapon to our armamentarium, offering the patient a treatment option that does not physically restrict or alter the anatomy, and is reversible.”