The U.S. Food and Drug Administration has approved the first weight loss treatment device, the Maestro Rechargeable System by EnteroMedics of St. Paul, Minnesota.
The implant is approved for adult patients who have been unable to lose weight with a weight loss program, and who have a body mass index (BMI) of 35 to 45 with at least one other obesity-related condition, such as type 2 diabetes.
The device consists of a rechargeable electrical pulse generator, wire leads and electrodes implanted surgically into the abdomen. Similar to a pacemaker, it sends intermittent electrical pulses to the abdominal vagus nerve, which is involved in regulating stomach emptying and brain signaling, to help control signals of hunger and fullness. The specific mechanisms for weight loss due to the device are unknown.
External controllers allow the patient to charge the device and allow health care professionals to adjust the device’s settings.
The safety and effectiveness of the Maestro Rechargeable System were evaluated in a clinical trial that included 233 patients with a BMI of 35 or greater who received either a device that was active or inactive (control). After 12 months, the experimental group lost 8.5% more excess weight than the control group. Half of the patients in the experimental group lost at least 20% of their excess pounds. The clinical study did not meet the original endpoint: a 10% greater weight loss in patients with the active device.
Serious adverse events reported in the clinical study included nausea, pain at the neuroregulator site, vomiting, as well as surgical complications. Other adverse events included pain, heartburn, problems swallowing, belching, mild nausea and chest pain.
The manufacturer will conduct a five year post-approval study to collect additional safety and effectiveness data.