MIT, working together with the Massachusetts General Hospital (MGH), has pioneered a method of drug distribution with the potential to dispense with traditional subcutaneous injections. The system uses a small capsule coated with microneedles in order to administer medicines directly into the lining of the intestine.
Ordinarily there is a challenge to orally administering drugs, in that rarely do they survive the acidic contents of the digestive tract long enough to effectively deploy their pharmaceutical payload. This problem becomes even more pronounced when working with drugs created from large proteins. Therefore, modern medicine has been forced to employ the frankly distasteful method of stabbing patients with tiny metal pipes and pushing medicine through the resultant wound. I think I speak for all of humanity when I say there has to be a better way.
The capsule measures 2 cm (0.8 in) in length and 1 cm (0.4 in) in diameter. It's designed with a central reservoir to house the drug, which is then injected into the intestinal tract lining via a series of 5 mm (0.2 in)-long mirconeedles that coat the outside of the pill. To aide with ingestion, as the capsule makes its way through the digestive system, the needles are protected by a Ph-responsive coating that dissolves upon reaching the intestine.
Crucially, the capsule's acrylic coating allows the drug to survive the inhospitable journey through the stomach with no degradation to the effectiveness of the pharmaceuticals contained inside. Furthermore, the design of the pill will allow it to be used for a multitude of different pharmaceuticals with no redesigning required, and the lack of any pain receptors in the lining of the GI tract means that patients would not even be aware of the needles delivering the medicine.
Animal testing for the capsule is already under way, with the team using the capsule to administer insulin to pigs. The results of the tests have been promising, with the pigs exhibiting no harmful side effects. Not only did the glucose levels present in the pigs' blood drop, thus proving that the capsule had successfully administered the insulin, but levels actually dropped more than those of pigs that were administered insulin with a traditional subcutaneous injection.
It is believed by the team that the capsule could have a wide range of applications, from treating autoimmune disorders such as arthritis to administering vaccines for conditions such as meningitis, that contain a biological component. Furthermore the pill could be used to deliver antibodies to cancer patients, representing an attractive alternative to the conventional treatment which involves a series of painful injections.
Looking to the future, the team hopes to further refine the capsule before moving to human trials. In this vein, the researchers are working to create a capsule with solid needles created from polymer and sugar. In this configuration, the medicine would be contained within the needles themselves, which are designed to break off from the pill and embed themselves in the lining of the GI tract. Once embedded in the wall, the needles slowly release the drug as they are naturally dissolved by the intestine. There are also plans to improve the efficiency of the pharmaceutical delivery process by using the natural contractions of the digestive tract to squeeze the medicine out of the capsule.
A paper detailing the team's work has been published online in the Journal of Pharmaceutical Sciences.
The video below, courtesy of MIT, outlines the benefits of the pharmaceutical delivery capsule.