Scientists in Melbourne have designed a new type of oral capsule that could mean painless delivery of insulin and other proteins.
Co-lead investigator Professor Charlotte Conn, a biophysical chemist at RMIT University, said protein drugs had proven difficult to take orally, as the drugs break down very quickly in the stomach, until now.
“These types of drugs are usually given by injection: thousands of diabetics in Australia require insulin injections multiple times a day, which can be unpleasant for the patient and lead to high healthcare costs,” said Conn, from the School of RMIT Medicine. Science.
He said the new technology could also be used to deliver other protein drugs orally, including a new type of oral antibiotic developed by the RMIT team that can prevent resistance from dangerous superbugs.
“Other protein drugs, such as monoclonal antibodies, have been developed to treat inflammatory conditions, cancer and other diseases with a projected market value of around $400 billion by 2030,” Conn said.
An international patent application has been filed for RMIT’s technology.
Strong preclinical results provide optimism for a new way to deliver insulin
The team has tested the new oral capsule with insulin in a preclinical study and the results have been published in the international journal Advances in biomaterials.
“We think the results are really exciting and we are running a suite of preclinical tests so we can move to clinical trials as soon as possible,” Conn said.
The research paper evaluated the performance of rapid- and slow-acting insulin oral capsules.
“When controlling blood sugar, you need a very quick response if you’re eating. That’s known as rapid-acting insulin,” Conn said.
A slow-acting form works over a much longer period of time, up to a day or so, to keep insulin in the body constant. Most diabetics take a combination of both types of insulin.
“We had excellent absorption results for the slow-acting form, about 50% better than administration by injection for the same amount of insulin,” Conn said.
The capsule achieved good absorption results for rapid-acting insulin, but the significant delay in insulin effect compared to injection would likely make it less practical.
“Our results show that there is real promise in using these oral capsules for long-acting insulin, which diabetics might one day take in addition to rapid-acting insulin injections,” Conn said.
“Oral capsules could potentially be designed to allow dosing for specific periods of time, similar to the administration of injections. We need to investigate this further, develop a way to do this, and undergo rigorous testing as part of future human trials.”
How does the team drug capsule work?
Dr. Jamie Strachan, the paper’s first author, said the capsule protected the drug inside so it would pass safely through the stomach and into the small intestine.
“The capsule has a special coating designed not to break down in the low-pH environment of the stomach, before the higher pH levels in the small intestine cause the capsule to dissolve,” said Strachan, of the College of Sciences of RMIT.
“We package the insulin inside a fatty nanomaterial inside the capsule that helps camouflage the insulin so it can pass through the intestinal walls.
“It’s actually similar to how the Pfizer and Moderna COVID vaccines work, where the mRNA from those vaccines is also packaged in fats, helping to keep the drugs active and safe during delivery in the body.”
These vaccines contain mRNA, which is similar to DNA, to safely carry the instructions for making a viral protein within the body, activating our immune systems.
A cheaper and more efficient way to administer protein drugs
Dr. Céline Valéry, a pharmaceutical scientist at RMIT and co-author of the study, said they used the same amount of insulin in the oral capsules and the injection.
“For many preclinical trials, oral formulations necessarily contain much higher levels of insulin to achieve the same response as administration by injection. This is not a very cost-effective way to deliver protein drugs that tend to be expensive,” Valéry said. , from RMIT’s School of Health and Biomedical Sciences.
“It’s a great starting point, but we need to do more trials to develop an alternative, painless method of administering insulin and other protein medications.”