In a new study entitled “Ultrasound-mediated gastrointestinal drug delivery,” a team of scientists report a new method using ultrasounds to deliver, fast and efficiently, drugs to the gastrointestinal tract. This strategy opens new potential therapeutic avenues for patients with inflammatory bowel disease (IBD). The study was published in the journal Science Translational Medicine.
Patients with IBD — a condition characterized by chronic inflammation of the digestive tract — have few treatments available, and these are usually administered as an enema (or clyster) directly into the colon. This approach, however, requires long hours for a drug to be absorbed, and its absorption is impaired in cases of diarrhea and incontinence.
Here, a team of scientists, following previous results where they showed that ultrasound could allow drug delivery through the skin, proposed to investigate if the system would enable the same through the gastrointestinal tract.
Robert Langer, the David H. Koch Institute Professor at MIT, member of the Koch Institute and one of the study’s co-lead authors, commented on a news release, “We’ve been working on ultrasound as a means to enhance transport through materials and skin since the mid-1980s, and I think the implications of this new approach have the potential to aid many patients.”
The team tested ultrasound-mediated drug delivery into the pig gastrointestinal tract — in which a fluid exposed to ultrasound waves generates bubbles that implode and function as micro jets toward a tissue, enhancing micro jets penetration. Authors discovered that ultrasound-enhanced absorption of two molecules of different sizes — insulin and mesalamine (used in treatments for colitis) — in the pig gastrointestinal tract.
“Demonstrating delivery of molecules with a wide range of sizes, including active biologics, underscores the potentially broad areas in which this technology could be applied,” said Carl Schoellhammer, a graduate student in chemical engineering and study first author in a news release.
Authors performed additional studies to test if this strategy could treat animal models of IBD. They showed that delivering mesalamine and immediately after applying ultrasound for one second every day for two weeks resolved colitis symptoms. Administering mesalamine without ultrasound, however, had no effect on animals’ symptomatic. Ultrasound-mediated delivery of insulin was found to be efficient at reducing blood sugar levels in pigs.
Daniel Blankschtein, the Hermann P. Meissner Professor in Chemical Engineering, and study lead author said of these findings: “With additional research, our technology could prove invaluable in both clinical and research settings, enabling improved therapies and expansion of research techniques applied to the GI tract. It demonstrates for the first time the active administration of drugs, including biologics, through the GI tract.”
The team of scientists is now optimizing the conditions for ultrasound-enhanced drug delivery in animals with the goal of testing it, in the future, in human patients.