Researchers have developed an implantable sensor that measures blood sugar continuously and transmits the information without wires — a milestone, they said, in diabetes treatment.

The device worked in one pig for more than a year and in another for nearly 10 months with no trouble, said a report in the journal Science Translational Medicine.
It takes the diabetes field a step closer to development of an “artificial pancreas” — a device that can replace natural functions to control how the body handles blood sugar.

And it would be handy for people who need to check blood sugar daily, such as patients with type 2 diabetes, the team at the University of California San Diego and nearby privately held GlySens Inc. wrote.

“You can run the device for a year or more with it constantly working and recording glucose quite satisfactorily,” bioengineering professor David Gough, who led the study, said in a statement.

“We hope to begin the first human trial in a few months,” Gough added in a telephone interview.

He said his team has been testing such experimental devices in pigs for 31 years.

Medical device makers have been working to develop a so-called artificial pancreas to deliver insulin to patients with type 1 diabetes, an autoimmune disease in which the body destroys its own ability to make insulin and thus to properly break down sugar.

Even with treatment, blood vessels and organs get damaged eventually, and patients can lose vision, organs and limbs. An estimated 3 million Americans have type 1 diabetes, usually diagnosed in childhood or in young adults.

Gough’s team said their device could also work for people with type 2 diabetes, which is far more common and increasing. An estimated 180 million people globally have diabetes.

The implant used in the pig study is about 1.5 inches  in diameter, and five-eighths  inch thick. “We hope to make it smaller in the future,” Gough said.

It transmits 10 to 12 feet.

The device uses a sensor that detects oxygen in the tissue in which it is implanted to measure glucose. “The present artificial pancreases use needle-like sensors or wire-like sensors,” Gough said. “This device is likely to be more appealing to people with diabetes. There is nothing protruding from the body.”

To inject insulin or use an insulin pump, patients need input on blood glucose levels. Too little insulin and patients get damage from hyperglycemia, or too much blood sugar.

Too much insulin and hypoglycemia — dangerously low blood sugar — can send patients into a coma.

Gough foresees ways to have the glucose monitor send its signals to cell phones.

“There are parents with diabetic children who spend their nights worrying that their child in a nearby bedroom may go into nocturnal hypoglycemia,” he said. An implanted sensor could wake a parent if the child’s glucose levels dropped to a dangerous level.

The Juvenile Diabetes Research Foundation, which helped pay for the study, has been working with several companies to create a seamless artificial pancreas. It works with  drugmaker Johnson & Johnson’s unit Animas, which makes insulin pumps, and DexCom Inc., which makes continuous glucose monitoring devices.

Smiths Medical, a unit of Smiths Group Plc , Abbott Diabetes Care, a unit of Abbott Laboratories Inc., and Medtronic Inc. also make glucose and insulin devices.

Gough and colleagues at the university founded GlySens, and the company collaborates with the institution.