Many aspects of our lives nowadays can be easily tracked on a smartphone, such as package deliveries, what our friends are doing, and our heart rates. Proteus Digital Health developed technology to add another item to this list: pill consumption. Oral medications can be turned into “smart pills” with the addition of a tiny sensor that emits an electric pulse once it reaches stomach acid [1]. The pulse is recognized by a patch that the patient wears on their torso, which in turn transmits its data to a smartphone. Pill consumption data can be tracked by the patient and whomever they give access to, such as their family or doctors. Abilify Mycite (aripiprazole), which can be prescribed for patients with bipolar disorder or schizophrenia, became the first medication approved by the FDA to use this technology [2]. One benefit of utilizing this technology in psychiatric medications is to prevent patients from taking multiple doses if they cannot remember taking their regular dose. Another exciting and widely applicable use of the smart pills is to improve adherence to medications.
Adherence is a critical component of medication delivery, especially in chronic diseases. Hypertension, diabetes, chronic kidney disease, HIV, and many other illnesses are best treated by consistent and correct use of prescribed medication. Meticulous drug dosing and pharmacokinetics curves are futile for non-adherent patients, who then do not gain the full benefit of their medications. Given access to their patients’ smart pill data, providers can track pill consumption and work with those who are not consistent. Some researchers have claimed that this technology can directly increase medication adherence in patients [3]. In their initial press release on ingestible sensors, Proteus Digital Health claims that this is important in “helping individuals to develop and sustain healthy habits” [4]. However, current research has not yet proven this claim, and further work must be done to investigate effects on adherence.
The use of smart pills is not the first technological innovation used to measure or improve adherence to medications. Smart pill boxes, which transmit data to apps that record when they are opened, have been used for years. The smart pill is a response to critics who point out that a patient can open a pill box and still not take medications. Phone notifications can be used as a stand-alone method to remind patients to take their medications, or it can be used in combination with smart pills or bottles. In an ideal world, digital monitoring of medications can reward patients who correctly use medications, and guilt patients who do not use medications into changing their habits. However, we know that this does not work with many patients. A personal example is when I got a Fitbit for Christmas in 2016. Through the wristband, my phone tracked steps taken each day and either rewarded me for hitting 10,000 steps or encouraged me to try harder when I failed. Once the admonishing notifications began noticeably outnumbering the congratulatory ones, I could no longer deny that I should walk more. To facilitate my denial, the Fitbit has been sitting in a shoebox since early 2017.
Ingestible sensors in pills can certainly have a use in medicine, as it is important for physicians to be able to track patient adherence to medication regimens. In a study on antipsychotic medication, patients and providers consistently overestimated adherence [5]. The study also found that adherence measures such as smart pill boxes and pill counting only weakly correlated with drug plasma levels. Improving adherence is an important goal in medicine, and establishing more valid and reliable measurements aids research efforts. Some medications are useless if not taken correctly and consistently, such as pre-exposure prophylaxis for HIV (PrEP). Unfortunately, the prevention drug has a notoriously low adherence rate. A research group from University of California, San Diego is studying the application of the smart pill technology to PrEP, with the implication that it may improve adherence [6].
The advent of new drug administration technology begs the question: what truly determines whether a patient will take their medications as directed? Smartphone apps and other technology has not yet been proven to be significantly impactful. Entire books have been written on the complex psychology of adherence, and certain principles appear to apply. Disease severity, treatment burden, emotional factors, and beliefs in healthcare are notable factors in individual adherence [7]. For example, people who see tangible benefits from medications are more likely to take them as prescribed, such as when patients see blood pressure improvements from hypertension medications. However, preventative medications like PrEP have no visible effect if they work correctly. This highlights the importance of providers taking the time to speak with patients about their chronic medications. Taking the extra time to investigate a patient’s health beliefs and motivations could help address psychological aspects of adherence, possibly negating the need for expensive technology to monitor medication intake.
[1] Rosenbaum L. Swallowing a Spy – The Potential Uses of Digital Adherence Monitoring. N Engl J Med. 2018;378(2):101-103. doi:10.1056/NEJMp1716206.
[2] FDA. FDA approves pill with sensor that digitally tracks if patients have ingested their medication. FDA Press Release. Published July 13, 2017. https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm584933.htm.
[3] Chen, J. Adherence to Prep, the HIV prevention drug, is low. A new study suggests a pill with a tiny sensor might help. StatNews. https://www.statnews.com/2018/07/24/digital-pill-prep-truvada/. Published July 24, 2018.
[4] Proteus Digital Health. Proteus Digital Health Announces FDA Clearance of Ingestible Sensor. https://www.proteus.com/press-releases/proteus-digital-health-announces-fda-clearance-of-ingestible-sensor-2/. Accessed November 5, 2018.
[5] Velligan DI, Wang M, Diamond P, et al. Relationships among subjective and objective measures of adherence to oral antipsychotic medications. Psychiatr Serv. 2007;58(9):1187-1192. doi:10.1176/ps.2007.58.9.1187.
[6] Abbasi J. HIV Preexposure Prophylaxis “Smart Pill” in Early Testing. JAMA. 2018;320(10):965. doi:10.1001/jama.2018.12335.
[7] Brannon L, Feist J, Updegraff JA. Health Psychology: An Introduction to Behavior and Health. 2017. Cengage Learning, 9th ed.
Luke Wohlford is a medical student in the University of Arizona College of Medicine - Phoenix, Class of 2022. He graduated from the University of Arizona in 2018 with a Bachelor of Science in physiology. Luke plans to go into emergency medicine has special interests in public health and EMS. He spends most of his free time hanging out with his dogs Kanye and Kelso or feeling guilty about not exercising.