Researchers at the MIT (Massachusetts Institute of Technology) and BWH (Brigham and Women's Hospital) have designed an innovative drug capsule. This drug capsule can remain in the stomach for up to two weeks after administration and continues to release the drug slowly. This way of releasing drugs can reduce the inconvenience of many therapies that require repeated medications, helping to overcome an important barrier to the treatment and elimination of many diseases, including malaria. The research was published in the latest issue of Science Translational Medicine.
At present, the efficacy of oral drugs is generally not effective in the body for more than one day. This is because they are quickly excreted from the digestive tract and need to face the harsh environment of the stomach and intestines. A drug capsule capable of achieving ultra-long-term drug release requires a long-term residence in the stomach to slowly release the drug and is resistant to gastric acid attack. At the same time, it needs to be decomposed and safely discharged from the digestive tract after the drug is released. These conditions pose great challenges to the design of drug capsules.
To meet these conditions, the researchers designed a starfish-like structure with six arms that can be folded centrally and packaged in a smooth-looking capsule. The drug is contained in six arms made of polycaprolactone, each of which is attached to a rubbery core through a special joint. These special joints are designed to be broken down over time. When the drug capsule is swallowed, the stomach acid in the gastric juice melts the outermost layer of the capsule, allowing the folded hexagonal star to unfold. The hexagonal star structure after the arm is deployed is large enough to resist the force of the stomach to move the object to the intestine, but not enough to cause harmful obstacles to the digestive tract.
In trials using pigs as a test subject, the researchers found that this new drug capsule maintained a slow and sustained drug release for two weeks. The joint that connects the six arms will then be dissolved, allowing the six arms to be separated from the core. The individual arms and core after decomposition are small and can be safely discharged from the intestines. In this study, the drug added to the capsule by the researchers is ivermectin, an anti-parasitic drug that, For example, a mosquito will die quickly when bites a person who has taken ivermectin. It can therefore significantly reduce the spread of malaria and other mosquito-borne diseases.
Professor Robert Langer of the MIT Koch Institute for Integrative Cancer Research, one of the co-authors of the study, said: "This technology opens the door to a very long-term oral drug delivery system that can be used to treat many diseases, such as Alzheimer's disease or mental health problems."
The results of this research have led to the establishment of Lyndra. The Cambridge-based startup will further develop the technology to treat diseases that best benefit from ultra-long-term, long-lasting drugs, including mental illness, AIDS, diabetes and epilepsy.
Reference:
New capsule achieves long-term drug delivery
Oral, ultra–long-lasting drug delivery: Application toward malaria elimination goals
