Electrical device to target obesity

CHICAGO — Within a few years, Americans may have a new tool to fight back against obesity: electricity.

Not from the power grid but from implanted pacemakerlike devices that influence a key nerve linked to food-related functions, including feelings of hunger and fullness.

The quest for obesity-fighting drugs and devices is a tricky area where companies have stumbled before, and hacking into the nervous system can prove challenging. But it's also a potentially huge market given the prevalence of obesity and the scarcity of useful, low-impact treatments.

Around one-third of Americans over age 20 are overweight enough to be considered obese, and the excess pounds are linked to other maladies, such as diabetes and heart disease.

Drugs have yet to play a significant obesity-fighting role, while invasive surgical procedures, such as gastric bypass, are a serious option for seriously endangered patients. Some medical technology companies have been chasing the implanted electrical-device angle to help fill the void.

Companies checking out the market include Medtronic Inc., St. Jude Medical Inc. and health-care giant Johnson & Johnson, which just signaled interest by buying the rights to patents for a nerve-stimulation technology from Cyberonics Inc.

But the company with the most attention-getting efforts here may be EnteroMedics Inc.

The company, based in St. Paul, Minn., is testing an implantable device called Maestro that periodically blocks transmission on the digestion-controlling vagus nerve. Limited study data suggests it may trigger significant weight loss. A bigger, yearlong randomized study that's enrolling over the next six months could put the company on track for U.S. approval in the middle of 2010, if things go well.

If approved, the technology could give weight-loss surgeons a significant new tool.

"A technology like this is dramatically safer than gastric bypass," said Scott Shikora, chief of bariatric surgery at the Tufts-New England Medical Center in Massachusetts, which will take part in the trial for Maestro. Shikora is a paid medical consultant for EnteroMedics.

Bypasses dramatically shrink the space for food and can lead to significant weight loss. But because of the severity and permanence of the procedures, and surgical risks, it's generally reserved for people more threatened by obesity itself, Shikora said.