An Insulin Pill? Researchers Present Lipid-Based Carrier at Meeting

Work on a lipid-based carrier that could safely transport insulin through the stomach, before it is absorbed in the bloodstream, was presented today at the 252nd meeting of the American Chemical Society in Philadelphia.

The technology, which researchers call a Cholestosome, is among several concepts being studied for protecting insulin from stomach acids before it reaches the intestines, where it could pass into the bloodstream. The concept would allow insulin to be administered in a pill form instead of injection, a fact of life for persons with diabetes.

Mary McCourt, PhD; Lawrence Mielnicki, PhD, and undergraduate Jamie Catalano of Niagara University presented their concept for a naturally occurring lipid molecule, which differs from other drug carriers under study. “Most liposomes need to be packaged in a polymer coating for protection,” Mielnicki said in a statement. “Here, we’re just using simple lipid esters (or compounds) to make vesicles with the drug molecules inside.”

The team presented computer modeling that showed the lipids assembled into spheres, forming neutral particles that are able to withstand attack from stomach acids. The spheres then reach the intestines, where they are recognized and absorbed. Once in the bloodstream, they break apart, and the insulin is released.

Researchers tested several insulin doses and pH levels until they found the optimal levels for animal testing. So far, tests with rats show that the insulin travels properly in the bloodstream, a concept known as “bioavailability,” or getting the drug where it needs to be. More tests are needed to fine-tune insulin levels before human trials can begin.

For years, diabetes researchers have looked for treatments to reduce the number of insulin injections, especially for children with type 1 disease at school or day care, where a nurse or other third party must administer insulin until the child is old enough for self-care. The inhaled insulin Afrezza has received enthusiastic reviews from patients, but some doctors have been reluctant to prescribe it due to concerns about the effect on the lungs, as well as FDA requirement for spirometry. Payer coverage has also been difficult for many patients.