Insulin pills near reality, promising injection-free diabetes care

A long-held dream in medicine is nearing reality as researchers at Kumamoto University have successfully developed insulin pills that survive the digestive system, potentially ending the need for daily injections for millions.

For years, scientists were unable to develop insulin pills due to the inability of the intestine to absorb insulin naturally into the bloodstream.

Moreover, enzymes in the digestive system break down insulin immediately before it can work. Given the hindrances, the recent breakthrough can be a game-changer in the treatment of diabetes.

In a recent revolutionary approach, the researchers utilized a cyclic peptide, known as the DNP peptide, that can pass through the small intestine, allowing insulin to be delivered orally in a way that was not possible earlier.

The team developed two effective strategies published in the journal Molecular Pharmaceutics, to ensure intestinal absorption of Insulin.

The mixing method

This approach relies on the physical association between insulin molecule and peptide without altering the chemical structure of insulin. When it comes to its efficacy, the mixture triggers a rapid return to healthy blood glucose levels when tested in chemically induced and genetic diabetic models.

The method also proved efficient enough to maintain stable glucose control with just one dose per day over a three-day period.

The conjugation method

This methodology is based on creating a permanent bond between the transport peptide and insulin. Using click chemistry, the team physically attached the DNP peptide directly to the insulin molecule to create a DNP-insulin conjugate.

The approach also achieved the same glucose-lowering success as the aforementioned method.

Limitations of oral insulin

Unlike injections, Insulin in oral form requires extremely high doses, more than 10 times higher than injections. But, this new platform also slashes such requirements and secure pharmacological bioavailability of about 33-41 percent compared to subcutaneous injection.

Future prospects

Given the significant pharmacological bioavailability of oral insulin, it is not wrong to assume that in near future oral insulin could be ready for real-world uses.

Associate Professor Shingo Ito said, “Insulin injections remain a daily burden for many patients. Our peptide-based platform offers a new route to deliver insulin orally and may be applicable to long-acting insulin formulations and other injectable biologics.”