Med Device Monday: Ingestible Event Marker

Over half of the adults in the U.S. suffer from a chronic disease or condition, such as heart disease or type-2 diabetes. Many chronic diseases and conditions can be managed through medication, but according to the World Health Organization, it is estimated that more than 50% of medications prescribed are not taken as directed. To measure treatment effectiveness and optimize therapies, health care providers would benefit tremendously from knowing how well a patient adheres to their treatment plan, including whether they actually take their medicine(s). Health care providers and a patient's loved ones don't want to be the pill police. However, knowing when/whether medication is taken can make it possible to determine the best course of action when it comes to treatment options.

To fulfill a previously unmet need, Proteus Digital Health (Proteus) developed a system that allows an individual to easily monitor their medication-taking patterns – as well as other important aspects of their health - and share that information directly with their caregivers and healthcare provider. The Proteus Discover system is comprised of four parts: an ingestible sensor the size of a sand grain, a patch that adheres to the torso and registers the sensor, a mobile application that records all data sent by the wearable patch, and with permission, a way for others to also see the collected information. Ingesting the sensor along with prescribed medication activates the Proteus Discover system. Once the sensor reaches the stomach, a signal is sent to the patch, which registers and relays the event to an app on the patient’s smart device, as well as a portal that can be made available to the patient’s caregivers and healthcare provider.

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There are many reasons why an individual may not take their medicine as directed; drugs may have undesirable side effects, or a patient may lack a complete understanding of their disease and the importance of taking their medication as prescribed. By having a way to recognize non-adherence and understand the underlying cause behind it, healthcare providers can quickly ascertain and respond to the issue. According to studies performed, use of the Proteus Discover system provides patients with “significantly improved and sustained outcomes.”

Individuals who suffer from schizophrenia, severe depression, and bipolar I disorder could really benefit from being held accountable for taking their medication. In 2015, Proteus teamed up with Otsuka Pharmaceutical Co., Ltd. (Otsuka), makers of the antipsychotic drug ABILIFY® (aripiprazole), to propose a new drug-device combination. Together, the companies submitted a New Drug Application (NDA) to the FDA for an Abilify tablet embedded with a Proteus ingestible sensor. At the time of submission, William H. Carson, M.D., president and CEO of Otsuka Pharmaceutical Development & Commercialization, Inc., stated that “patients suffering from severe mental illnesses struggle with adhering to or communicating with their healthcare teams about their medication regimen, which can greatly impact outcomes and disease progression.” The combination product was proposed to provide an opportunity to objectively measure medication adherence, as well as other aspects of the patient’s health as collected by the Proteus patch.


Although both Abilify and the Proteus Discover system are independently FDA approved, after months of review, FDA rejected the NDA for the combination product. The companies were given a Complete Response Letter (CRL), a non-public document issued by the FDA that outlines the additional steps a non-approved drug must take to secure approval. According to an article in MobiHealth News, Otsuka and Proteus, FDA asked for "data regarding the performance of the product under the conditions in which it is likely to be used, and further human factors investigations." While the setback was no doubt disappointing, it is likely we have not seen the last of the combination product, and that efforts are ongoing to provide FDA with the safety and efficacy data required to approve the drug-device combination.