The days of self-administered insulin injections may be coming to an end. Researchers from MIT have devised a means of insulin delivery previously thought impossible—a simple pill. Up until now, oral delivery was a no-go, as large protein drugs such as insulin are unable to cross the mucus barrier present in the digestive system. Now, however, the pill dubbed “RoboCap” can tunnel through this barrier and make its way to the small intestine, transferring its passenger drugs into the cells lining the intestine.
"I thought that if we could tunnel through the mucus, then we could deposit the drug directly on the epithelium," said the product’s inventor, Shriya Srinivasan, a research affiliate at MIT's Koch Institute for Integrative Cancer Research and a junior fellow at the Society of Fellows at Harvard University. "The idea is that you would ingest this capsule, and the outer layer would dissolve in the digestive tract, exposing all these features that start to churn through the mucus and clear it." Srinivasan was the lead author of the study on RoboCap, which was published in Science Robotics on September 28. Initial development entailed honing a protective capsule containing a mechanism that could tunnel through mucus, akin to the functionality of actual tunnel-boring machines that work their way through soil and rock.
The new pill is roughly the size of a multivitamin, and its tunneling features are positioned both in its main body and in its surface. It holds its medicinal payload in a reservoir at one end, with a gelatin coating that disintegrates at a predetermined, specific pH level—triggering the capsule’s nearly microscopic motor to spin and burrow into the mucus layer.