In the evolution of computing, from the desktop computer to the smartphone to the watch, it seemed like just a matter of time before the technology would come to be swallowable — and now it is. The innovation at the heart of it is an FDA-approved ingestible sensor housed in pills, designed to help patients adhere to the medications their doctors prescribe. Except the sensor isn't powered by a battery, it's powered by the gut of the patient swallowing it, using technology discovered two centuries ago. "We have a small, food-particle-sized piece of silicon, an integrated circuit, and on one side of that circuit is a film of copper, on the other side a very thin film of magnesium," explained Proteus Digital Health co-founder Dr. George Savage. "When you swallow, these minerals get wet and two dissimilar metals in aqueous contact define a battery, so you become a battery." From there, the powered pill sensor sends a signal to a patch worn on the body, which sends data via Bluetooth to a phone or tablet and on to the cloud for a doctor or caregiver. (Tweet This)



A digital sensor the size of a grain of sand is housed in a pill. After being swallowed, its signal is picked up by a patch worn on the body, which relays data to a phone or tablet. Source: Proteus Digital Health

The patient-as-a-battery idea sounds simple enough, and the company likens the process to a child's science-fair experiment, but this one garnered more than 350 patents and received more than $400 million in funding from some of the biggest names in health care, including Novartis, Medtronic, Kaiser Permanente at a unicorn valuation. "What's the most common thing that somebody who is sick is supposed to do every day? Swallow their medicine," Proteus CEO Andrew Thompson told CNBC. The only problem is, they don't. According to the World Health Organization, about half of all patients with chronic illnesses, such as cardiovascular disease or high blood pressure, fail to take their medications as prescribed. By some estimates, such nonadherence in the U.S. can add up to 10 percent of hospitalizations in older adults, costing the health-care system $100 billion to $300 billion.

Proteus Digital Health CEO Andrew Thompson Qin Chen | CNBC

"If you give people, for example, five medications to take a day and you say take this in the morning, take this at lunch time, take this in the evening, that's very complicated," Thompson said. "So what we're showing is the beginning of a solution … to one of the single biggest problems in all of health care, which is to help you take your medicines appropriately." In the latest of Proteus' 67 clinical trials, preliminary results demonstrated that patients suffering from uncontrolled high blood pressure who were prescribed the digital pill had "dramatically lower blood pressure … with about 85 percent of patients at four weeks in the Proteus groups achieving their goal, versus about 33 percent in the usual care group," Savage said.

If I'm taking pills to control my hypertension, that's one thing, but if I'm taking pills to control my drug addiction, who gets to see that and who knows about it is a very different thing. Arthur Caplan NYU professor and bioethicist

Noting the differences between tech and health care, Thompson said the company isn't looking to expand its services too quickly, only starting its first use outside of a clinical setting this January with hundreds of patients and their doctors at South Lake Tahoe, California–based health system Barton Health, before looking into licensing the technology to big pharma companies. While the implications have many in the medical field excited at possibilities, questions surrounding the technology have shifted from "will this work?" to "how will this be used?"

Barton Health patient Lori Caldwell is among the first to use Proteus outside of a trial setting. Qin Chen | CNBC

"If I'm taking pills to control my hypertension, that's one thing, but if I'm taking pills to control my drug addiction, who gets to see that and who knows about it is a very different thing," New York University bioethicist Arthur Caplan told CNBC. "I think there are vulnerable groups out there for whom this technology might not be seen as the world's biggest gift."

