Nano carrier could enable oral insulin for diabetics

A research team led by The University of Sydney (USyd) has used nanotechnology to develop a new type of oral insulin, which could offer a needle-free approach to managing diabetes. The researchers say their oral insulin, described in the journal Nature Nanotechnology, could be contained in a tablet or even embedded within a piece of sugar-free chocolate.

It is estimated 422 million people worldwide have diabetes and approximately 75 million of these inject themselves with insulin daily. But the development of a safe and effective form of oral insulin has been a challenge since insulin was discovered over a century ago, as noted by USyd’s Dr Nicholas Hunt.

“A huge challenge that was facing oral insulin development is the low percentage of insulin that reaches the bloodstream when given orally or with injections of insulin,” Hoult said. “To address this, we developed a nano carrier that drastically increases the absorbance of our nano insulin in the gut when tested in human intestinal tissue.”

The team’s oral insulin utilises a nanoscale material that is 1/10,000th the width of a human hair. This material acts similarly to acid-resistant coating on tablets — which protects them from being destroyed by stomach acid — but instead surrounds individual insulin molecules and becomes a nano carrier, acting like a courier to ferry these molecules to the places they need to act.

Studies in mouse, rat and baboon animal models have shown that the greatest strength of the nanoscale material is that it can react to the body’s blood sugar levels. The coating dissolves and releases the insulin only when there is a high concentration of blood sugar, not in low blood sugar environments. There is also no toxicity or weight gain.

“Our oral insulin has the added benefit of greatly reducing the risk of hypoglycaemic episodes,” Hunt said, referring to a low blood sugar event where too much insulin has been injected. “For the first time, we have developed an oral insulin that overcomes this major hurdle.”

Human trials are expected to start in 2025, led by spinout company Endo Axiom.

Image caption: R&D version of the oral insulin capsule. Image credit: University of Sydney/Stefanie Zingsheim.