The pill at the size of a pea injects insulin into the inside of the stomach

by LAURAN NEERGAARD, AP Medical Writer

WASHINGTON (AP) – Scientists have discovered how to hide a bullet in a pea-sized pill, creating a swallowing gadget, inspired by a turtle shell, capable of injecting drugs like insulin in the stomach.

Patients generally prefer oral treatments and conform to them better, but many compounds, including insulin for diabetes, can not survive this difficult journey into the digestive system.

The new invention, reported Thursday by a research team led by MIT, has only been tested in the animal. But if that happens, it could offer a way around the problem to make not only insulin, but also a variety of drugs usually injected, easier to take.

"It's like a miniaturized rocket launcher" for insulin, said Willem Mulder of the Mt. Sinai Translational and Molecular Imaging Institute, which did not participate to the new search.

Scientists have spent decades trying to develop oral insulin and replace at least some of the daily injections required by many people with diabetes. Attempts include ways to protect insulin from digestive degradation, and then help it to be absorbed by the intestine into the bloodstream. Until now, none has reached the market, although some closely watched candidates are being tested.

Dr. Giovanni Traverso, a gastroenterologist at Brigham & Women's Hospital in Boston and lead author of the study, says that an injection by ingestion could avoid the vagaries of this trip – let the insulin absorb through the wall of the stomach.

"The way it works is to cross the esophagus in a few seconds, in the stomach in minutes, then you get the drug," said Traverso, who worked with a laboratory team of the # 39, inventor of MIT, Robert Langer, and the insulin manufacturer. Novo Nordisk.

First challenge: how to make sure that the aircraft lands at a place where it can be placed in the right place, even if someone is moving. The researchers looked for ideas in nature.

A certain turtle, the African leopard tortoise, can straighten up if it is turned over on the back thanks to the pronounced curve of its shell. The researchers have developed a miniature capsule of similar shape and weighted bottom, so that once it reaches the stomach, it automatically rolls in the right direction to allow the snap, explains Traverso.

The team then designed a micro-injector, similar to a needle made only of dried insulin and compressed into a tapered tip. To feed it, the researchers tied a tiny spring to a hardened sugar disc.

The stomach acid gradually dissolves the sugar until the spring, throwing insulin into the wall of the stomach.

In swine, the unmanageable injection lowered blood sugar levels to levels comparable to conventional vaccines, according to a study published Thursday in the journal Science.

Once the insulin was absorbed, the capsule, made of stainless steel and a biodegradable material, floated freely and was excreted.

"It's a very smart idea, intended to solve a long-standing problem," said Steven Little, chairman of the Chemical Engineering Council of the University of Pittsburgh, who also did not participated in the research. Because the gadget goes through, "the only thing administered to the body is this little injector".

An obstacle: it works on an empty stomach, nothing can interfere with the locking of the device. Traverso said it would mean that it could someday replace morning insulin injections, but not the doses after meals.

Traverso explained that gastroenterologists have long been using larger needles to administer medications during some gastric procedures and that their patients are recovering well. The stomach muscle is thick enough not to worry about the perforation of a microinjection, and studies in the animal have revealed no side effects. Traverso added, however, that more research is needed to determine how the stomach handles multiple microinjections daily.

Additional studies on animals are underway and Traverso hopes that human testing can begin within three years.