Oral Form of Insulin Delivery Shows Promise at Expo

Experiments with rats showed that specially engineered polymer patches attached to the intestine and delivered insulin.

A new method of delivering insulin, which deploys an intestinal patch containing the hormone in a capsule, has proven effective in managing blood sugar levels in rats, based on a presentation this week at the 2015 American Association of Pharmaceutical Scientists, taking place in Orlando, Florida.

Researchers from the University of California at Santa Barbara, led by Samir Mitragotri, PhD, a professor of engineering, and Amrita Banerjee, PhD, a postdoctoral fellow, developed polymer technology to load the patches with insulin and contain them in a capsule that dissolves, which releases the patches so they can attach to the intestinal wall to for site-specific insulin release.

The adhesive strength of the patches was tested using pig intestines before experiments with rats. First, diabetic rats fasted before being fed capsules with the insulin-loaded capsules. Blood glucose levels were tested at intervals over an 8-hour period using a commercial blood glucose meter to measure the drop in glucose levels.

Experiments showed that all the insulin released within 5 hours, and researchers were able to gauge the enhancements to the patches to determine which made them adhere to the intestines especially well.

“Diabetes is a growing problem in the US, with new survey data showing that 50% of adults in the US have diabetes or prediabetes,” said Banerjee. “The outcome of our studies suggest that this unique drug delivery approach could be used to delivery insulin orally in a continuous, time-dependent manner.”

Additional testing will be done to evaluate how the patches can be used for rapid or extended release of insulin, as well as use of the patches for other diabetes drugs, such as exenatide.