It’s well known that the fear of injections leads some patients to forgo visits to the doctor or to stop adhering to home treatment regimens. But now researchers at MIT and Massachusetts General Hospital are working on a device that would circumvent such fears for at least some shot-takers.
Their microneedle pill is a spiky oral capsule containing a dose of a drug that is normally injected into muscle tissue because the drug molecule is too large to be absorbed through the walls of the gastrointestinal tract. Once the capsule reaches the appropriate place in the tract, its pH-sensitive end dissolves, causing the drug to be pushed out through the intestine wall via the pill’s microneedles. Such microinjections have the added benefit of requiring smaller drug doses than muscle injections.
The capsule has been successfully tested with insulin in pigs, and the researchers are working on enhancements for use in humans. The needles could be made out of a biodegradable sugar that would dissolve while releasing the drug, for instance, or out of materials allowing timed release. The device may even make vaccines more effective because the large number of immune cells in the GI tract should elicit a stronger immune response than those within muscle tissue.
Animal tests are estimated to last another two to five years before human tests can begin, but the researchers are patient. Study co-author Carl Schoellhammer is reassuring, saying, “The ultimate goal is to get this to patients.”
