A group of researchers at the University of British Columbia says they are one step closer to developing a pill that could deliver insulin as effectively as an injection.
If they are successful, it could mean the end of daily insulin injections for many diabetic patients.
Recent results from testing on rats found that the insulin from the oral tablets were absorbed by the rats in the same way as injected insulin, leaving virtually no insulin behind in the rats' stomach.
"[The insulin] was all in the liver and this is the ideal target for insulin — it's really what we wanted to see," said PhD candidate Yigong Guo, who is working closely on the project.
The project's lead, Anubhav Pratap-Singh, was inspired to pursue the research by his father, who lives with Type 2 diabetes.
"For the last 14 to 15 years, he has been taking [injected] insulin every day," said Pratap-Singh. "The current approach of injecting insulin every day brings a lot of pain to the patients and their family members."
Diabetes is a disease in which a person's body either can't produce insulin (Type 1) or can't properly use the insulin it produces (Type 2).
Insulin is a hormone produced by the pancreas. It's needed to control the amount of glucose, or sugar, in the blood. Insulin deficiency can lead to increased blood sugar and serious health problems, such as blindness, heart disease, kidney problems, amputation, nerve damage and erectile dysfunction.
According to Diabetes Canada, the only ways to administer insulin currently are through injections with pens, syringes, or pumps. Depending on their specific diagnosis, patients might start on one or more injections each day, or even before every meal.
There are several other methods of administering insulin in development. In 2019, researchers at MIT developed a capsule that could be used to inject up to 300 micrograms of insulin.
Pratap-Singh said the oral tablets his team is developing would deliver insulin effectively through the buccal region — the area in the mouth behind the cheeks and around the gums.
"We saw that the buccal region is something which actually gives a very similar profile to injected insulin," he said.
"Keeping it in the buccal region allows us to deliver the insulin for a period of 40 to 45 minutes through a slow release mechanism. So that means that the efficacy is extended quite a bit."
According to the UBC researchers, most swallowed insulin tablets in development tend to release insulin slowly over two to four hours, while fast-release injected insulin can be fully released in 30 minutes to two hours.
The medical director of B.C. Diabetes believes the pills could have great benefits for many diabetics if the researchers are successful.
"I have, I think, 2,500 patients who inject insulin every day," said Tom Elliott, who is also a physician and career endocrinologist. "And if I told them that they could take a pill or hold a capsule in their cheek until it dissolves I think they'd get pretty excited."
Elliott has been aware of the project for some time and has assisted the researchers in applying for grant money.
However, he says the results of the experiments on rats show insulin delivery occurred within 30 minutes of taking the pill and diabetics need insulin much more quickly.
"It's not going to give very fine regulation the way insulin pumps do and the artificial pancreas does in people living with Type 1 diabetes."
Pratap-Singh says their fast-release oral tablet has obvious benefits to people with diabetes. Reducing the need for injections would also eliminate environmental waste from the needles and plastic from the syringe that might not be recycled and go to landfill, he says.
The pills could also be more easily stored and transported than injected insulin, which must be refrigerated.
Pratap-Singh says now that trials have been conducted on small animals, they will need to test the tablets with larger animals before conducting any human trial.