To heal and to protectProteus Digital Health, a startup whose signature product is an ingestible pill sensor that can help track medication compliance, announced that it has raised nearly $200 million dollars in its latest funding round.

By some estimates, medication noncompliance contributes to over 100,000 deaths per year in the United States alone and costs the healthcare system hundreds of billions of dollars1. Investors, including Medtronic and Novartis, are making big bets that the technology pioneered by Proteus will help change that – and perhaps capture some of that value along the way.

The ingestible sensor, or event marker as described in studies of the device, is comprised of a microcircuit embedded within layers of minerals and metals all coated with cellulose. When the pill enters the stomach, the acidic fluids power an embedded biogalvanic battery that creates an electrical field that can transmit a unique identifier through the body tissue to a wearable patch.

The patch, which also collects biometric data like heart rate and movement information, uses Bluetooth to transmit the time-stamped signal and unique identifier to a smartphone or tablet with the company’s HIPAA compliant app installed. [For more details, check out the recent paper in Transplantation describing use of the system in renal transplant patients 2]

Currently, use of the ingestible sensor remains a little tricky. Either the patient has to basically take a second pill every time they take the pill of interest or a specialty pharmacy has to combine their actual medication with the sensor into some time of capsule. Frankly doubling the number or size of pills does not seem like the best thing to do when you’re worried about medication compliance; that beings said, the long term plan is probably to embed this technology into medications from the start.

There are several advantages here over simply using apps that track medication compliance or even electronic pill boxes. First, apps and electronic pill boxes can be manipulated – I’ve heard of patients simply opening and closing the pill box to avoid the “take your medicine” call. Secondly, those methods ask even more of a patient who is already having trouble remembering to do what we’ve asked. Using an ingestible sensor and patch, medication adherence tracking becomes less onerous and more objective.

Through Proteus’ Helius platform, the data captured can be shared with both the patient’s physician and care team as well as their families and caregivers. Having seen the effect that strong social supports can have on a patient’s care, engaging families and caregivers in this platform could be a really powerful way to promote medication adherence.

Proteus is currently enrolling clinical trials to demonstrate the impact of this platformsuch as a study underway at UC San Diego comparing Proteus’ digital monitoring system to direct observed therapy for TB patients. What remains to be seen is whether use of this system can appreciably improve medication compliance in a way that makes an impact on outcomes. If this system increases compliance with, say, diabetes medications by 10% but that doesn’t improve glycemic control or reduce downstream complications of diabetes then it may simply not be worth it. Trials like those being conducted as UC San Diego will be critical to determining whether clinicians should be as excited as investors.