The device, known as the Maestro Rechargeable System, is approved to treat patients aged 18 and older who have not been able 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.

　　BMI, which measures body fat based on an individual's weight and height, is used to define the obesity categories.

　　The Maestro Rechargeable System is the first obesity device to be approved by the FDA since 2007.

　　U.S. regulator approves first-of-kind device to treat obesity

　　"Obesity and its related medical conditions are major public health problems," said William Maisel, deputy director for science and chief scientist with the FDA's Center for Devices and Radiological Health, in a statement. "Medical devices can help physicians and patients to develop comprehensive obesity treatment plans."

　　The device, manufactured by EnteroMedics of St. Paul, Minnesota, consists of a rechargeable electrical pulse generator, wire leads and electrodes implanted surgically into the abdomen.

　　It works by sending intermittent electrical pulses to the trunks in the abdominal vagus nerve, which is involved in regulating stomach emptying and signaling to the brain that the stomach feels empty or full.

　　In a 12-month clinical trial that included 233 patients with a BMI of 35 or greater, those who received the active Maestro device lost 8.5 percent more of the excess weight than who received the device that was not activated.

　　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 FDA said.

　　The clinical study did not meet its original goal, which was that those who received the active Maestro device lose at least 10 percent more excess weight than the control group.

　　However, the FDA said its advisory committee found the study supportive of sustained weight loss, and agreed that the benefits of the device outweighed the risks for use in patients.

　　As part of the approval, the company must conduct a five-year post approval study that will follow at least 100 patients and collect additional safety and effectiveness data including weight loss, adverse events, surgical revisions and explants and changes in obesity-related conditions, the agency added.

　　According to the U.S. Centers for Disease Control and Prevention, more than one-third of all U.S. adults are obese, and people with obesity are at increased risk of heart disease, stroke, type 2 diabetes and certain kinds of cancer.