There is a new development on the horizon – a drug capsule that can deliver oral doses of insulin. This recent development by an MIT-led research team has the potential to replace the injections given to type 1 diabetic patients on a daily basis.
The capsule is almost the size of a blueberry. It contains a small needle composed of compressed insulin. This needle is injected after the capsule reaches the stomach.
When tested on animals, it was found that the capsule could deliver more insulin than that injected through the skin, which would result in a more efficient reduction of blood sugar. When tested on pigs, up to 5 milligrams of insulin could be successfully delivered, and the amount is comparable to what a type 1 diabetic patient would need to inject.
The researchers moreover demonstrated the device’s capability of being adapted to deliver other protein drugs.
We are really hopeful that this new type of capsule could someday help diabetic patients and perhaps anyone who requires therapies that can now only be given by injection or infusion – Robert Langer, a Professor of the David H. Koch Institute, a member of MIT’s Koch Institute for Integrative Cancer Research, and one of the senior authors of the research.
Other notable figures that comprise the research group are Giovanni Traverso, Alex Abramson, scientists from the pharmaceutical company Novo Nordisk.
Some years back Langer, along with Giovanni Traverso and several other colleagues, had developed a pill coated with numerous tiny needles that could be used to inject drugs into the lining of the stomach or the small intestine. The difference between the older pill and the new capsule is that the new capsule contains just one needle that can avoid injecting drugs into the interior of the stomach where stomach acids would break them down before the drugs can have any effect whatsoever.
The capsule is made from biodegradable polymer and stainless steel components. The capsule’s needle is attached to a compressed spring held in place by a disk composed of sugar; the water in the stomach dissolves the sugar disk which then releases the spring and injects the needle into the stomach wall.
The needle comprises nearly 100 % compressed, freeze-dried insulin, and the shaft of the needle that does not enter the stomach wall is made from a biodegradable material.
The stomach wall containing no pain receptors, patients would not be able to feel the injection piercing, according to the researchers. Moreover, the capsule system has been designed in such a way that it can orient itself in a way that would allow the needle to be in contact with the stomach lining, no matter how the capsule lands in the stomach.
As soon as you take it, you want the system to self-right so that you can ensure contact with the tissue. – As per Traverso
The inspiration for this self-orientation feature for the researchers comes from the leopard tortoise whose shell contains a high, steep dome, allowing it to right itself if it rolls onto its back. With the help of computer modeling, the researchers created a variant of this shape for the self-orienting capsule.
“What’s important is that we have the needle in contact with the tissue when it is injected,” Abramson says. “Also, if a person were to move around or the stomach was to growl, the device would not move from its preferred orientation.”
When the tip of the needle is injected, the insulin dissolves at a rate that is controllable by the researchers. For instance, in the present study, releasing all of the insulin into the bloodstream took about an hour.
After animal testing, it was found that upon releasing its contents the capsule can pass harmlessly through the digestive system. No adverse effects were found, either.
Maria José Alonso, a professor of biopharmaceutics and pharmaceutical technology at the University of Santiago de Compostela in Spain, who describes the new capsule as a “radically new technology” that could benefit many patients, further remarks that, “We are not talking about incremental improvements in insulin absorption, which is what most researchers in the field have done so far. This is by far the most realistic and impactful breakthrough technology disclosed until now for oral peptide delivery.”
The MIT team is now working with the pharmaceutical company Novo Nordisk for further development of the technology and optimization of the capsules manufacturing processes. They also would conduct further research into this type of drug delivery that has the potential to deliver protein drug to the inside of the body, such as immuno-suppressants used to treat rheumatoid arthritis or inflammatory bowel disease, and even nucleic acids such as DNA and RNA.
According to Traverso, “Our motivation is to make it easier for patients to take medication, particularly medications that require an injection… The classic one is insulin, but there are many others.”
The research was funded by Novo Nordisk, the National Institutes of Health, a National Science Foundation Graduate Research Fellowship, Brigham and Women’s Hospital, a Viking Olaf Bjork Research Scholarship, and the MIT Undergraduate Research Opportunities Program.