The writer is a science commentator
The old term was “compliance”; today, the preferred label is “adherence”. Whatever you call it, getting patients to keep taking their meds is a big deal.
First, it benefits the patient: non-adherence accounts for an estimated 125,000 preventable deaths per year in the US, many from controllable conditions such as HIV and type 2 diabetes, plus at least $100bn in healthcare costs. Second, private lapses matter for public health: drug-resistant strains of tuberculosis have emerged triumphant from half-finished treatment courses.
Now scientists at the Massachusetts Institute of Technology claim to be one gulp closer to tackling the problem, by creating an experimental pill that sends a radio signal to report it has been swallowed. The signal is detected locally and then sent on to health staff, with a missing signal prompting a reminder or an alert. While digital pills have appeared before, the touted leap forward here involves electronics that disappear after being taken. The MIT smart pill is mostly “bioresorbable”, which means it can break down in the body.
But while we should welcome innovations that make it easier to stay healthy, we should also recognise the subtle shift that happens when pills become messengers as well as medicines. Digital treatments “reinforce the framing of non-compliance as the fault of the patient rather than of the healthcare team, supply chain or medication itself”, observes bioethicist Richard Ashcroft of City St George’s University of London, adding they should not replace the human touch. Smart pills also raise obvious issues of privacy and autonomy, as the MIT researchers themselves recognise, given sensitive medical information is telegraphed to third parties.
The experimental pill, so far tested only in animals and reported in Nature Communications this month, comprises a capsule containing a zinc RFID antenna wrapped in cellulose, a natural plant polymer. The capsule’s outer layer is made of gelatin, cellulose and a signal-blocking substance like molybdenum.
Swallowing it causes the coating to dissolve, which releases the antenna. This activates a radio-frequency tag, providing a time stamp for ingestion to be picked up by a nearby reader, like a wearable patch, and transmitted onwards.
Preliminary studies in pigs showed the tag activated within an hour of hitting the gut. All the ingredients broke down in the body over 24 hours except for the sub-millimetre RFID tag, presumed to have been excreted out.
Giovanni Traverso, a gastroenterologist and co-author of the paper, said the passive, degradable system avoided the safety concerns of existing digital pills, with no batteries or electronic components left in the body. Measured levels of zinc and molybdenum afterwards were recorded as being within the bounds of dietary variation.
Further work would need to prove the pills can work long term in people. The project received funding from the Advanced Research Projects Agency for Health (Arpa-H) and pharma company Novo Nordisk; three authors, including Traverso, are named as co-inventors on a patent application.
For now, he explained, the proof-of-concept targets conditions for which missed doses carry considerable risks: neuropsychiatric illnesses; tuberculosis; HIV; immunosuppression for transplant patients, to stave off organ rejection; some cases of cancer and cardiovascular disease. The system can, however, be spoofed by dissolving the capsule outside the stomach, so deploying it requires guarding against false positives.
There are other barriers to wider adoption: feasibility, cost, miniaturisation and regulatory acceptance. The technology, Traverso recognised, “raises legitimate concerns about privacy, consent and autonomy . . . and [we] see ethical oversight and engagement with patients and ethicists as essential steps in clinical translation”.
In short, digital pills still need patient buy-in. It is worth asking: why do some find it hard to reliably take their pills in the first place? The American Medical Association lists many reasons: fear of side-effects; worries about cost; not understanding why they are necessary, especially for chronic rather than acute diseases; a perceived lack of symptoms; confusion when taking multiple medicines; a suspicion of doctors, drugs or drug companies; concerns over dependency; depression.
None of this means that digital pills are a dead end; they could furnish valuable insights into real patient behaviour. But social, economic and cultural fixes matter too.