New hydrogel-based capsules that remain in the gastrointestinal tract and slowly release medications could help patients stick to their treatment regimens.
Poor adherence and non-adherence (patients taking their medications improperly, or not at all) are associated with worse therapeutic outcomes, progression of disease, and an estimated burden of billions of dollars per year in avoidable direct health costs1.
The issue is particularly prevalent in people with chronic conditions, who often need to take multiple medications each day.
Researchers at the Massachusetts Institute of Technology (MIT) and Brigham and Women’s Hospital are in the early testing stages of developing hydrogel-based capsules, which they call triggerable tough hydrogels (TTH). The material they are made from enables them to remain in the gastrointestinal tract and slowly release medications over time.
Creating an effective capsule is difficult, as most materials cannot withstand the compressive forces in the stomach. At the same time, the capsule needs to be small enough to swallow, but large enough not to pass through the stomach, and also able to self-destruct on command in cases of allergic reaction.
The product uses polymer gels that swell in the stomach to prevent them passing through. Their molecular structure makes them more resilient to compression, and they are designed to dissolve when another solution is swallowed.
First, the researchers tested the mechanical strength of their solutions. They found the TTHs were strong enough to resist pressure from a razor blade.
Testing in animal stomachs showed that the capsules could remain for up to seven days. Further experimentation with the capsules as a possible drug delivery mechanism for malaria medicine showed that the devices released the medicine in a controlled manner over several days.
Solving the problem of medication adherence could benefit the U.S. healthcare system hugely. According to recent research, non-adherence costs it $100-$300 million per year – around 3-10 percent of total U.S. healthcare costs2.
Although the capsules created in this study are in their preliminary testing stages, they could offer a promising solution to the problem of poor and non-adherence – not only in the U.S. but around the world. The potential extra benefit of delivering medication could also prove revolutionary in how treatments are given, particularly for conditions that require dosing over time.
The researchers plan to investigate the medicine-release capability of the capsules, as well as their use in weight loss and tissue engineering.
Michael Mitchell, Jamie Webster, Amanda Chung, Pedro PG Guimarães, Omar F. Khan, and Robert Langer. Polymeric mechanical amplifiers of immune cytokine-mediated apoptosis. Nature Communications 2017; 8.
1 Robin DiMatteo. Variations in patients’ adherence to medical recommendations: a quantitative review of 50 years of research. Medical care. 2004;42(3) 200-209.
2 Aurel Iuga, Maura McGuire. Adherence and health care costs. Risk management and healthcare policy. 2014;7(35).