Pill injects insulin from inside stomach

WASHINGTON — Scientists figured out how to hide a shot inside a pea-sized pill — creating a swallowable gadget, inspired by a tortoise shell, that can inject medicines like insulin from inside the stomach.

Patients usually prefer oral treatment and comply with it better, but many compounds, including insulin for diabetes, can’t survive the harsh trip through the digestive system.

The new invention, reported Thursday by a Massachusetts Institute of Technology-led research team, has been tested only in animals so far. But if it pans out, it might offer a work-around to make not just insulin but a variety of usually injected medicines a little easier to take.

“The way this works is it travels down the esophagus in seconds, it’s in the stomach within a few minutes, and then you get the drug,” said Dr. Giovanni Traverso, a gastroenterologist and a senior author of the study.

First the team designed the pill with a rounded shape and weighted bottom, a design based on the shell of an African tortoise, so it will roll to the right spot in the stomach to inject the medicine.

Next the team designed a micro-injector, a needle made of dried insulin. It’s powered by a tiny spring connected to a hard sugar disk, which dissolves in stomach acid, triggering the injection.

In pigs, the ingestible injection lowered blood sugar to levels comparable to standard shots, according to the study.

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

“It’s a very clever idea that is meant to solve a very long-standing problem,” said University of Pittsburgh chemical engineering professor Steven Little, who wasn’t part of the research.

Additional animal studies are under way, and Traverso hopes human testing can begin within three years.