17 October 2002

The need to take medicines such as insulin and vaccines by injection could soon be a thing of the past, thanks to advanced research at The University of Queensland.

Professor Istvan Toth of the School of Pharmacy is leading a project to develop a new delivery system for peptide drugs. It would enable many injectable medicines to be replaced with tablets.

The research, funded by grants worth about $2 million, is in an advanced pre-clinical phase. Testing on humans could begin within three years.

Professor Toth’s research group has come up with a method that chemically alters peptides with special lipids and sugars.

“Peptides are our body’s natural building blocks,” Professor Toth said. “Peptide drugs such as insulin and sex hormones regulate our natural body functions. They currently can’t be administered orally, and have to be injected.”

The team’s method uses lipids to make the peptide compounds more stable, and able to move through different biological membranes intact, such as the gut wall.

Sugars are added to make the compound more soluble, making handling easier.

Professor Toth said the combination would also enable compounds to be targeted into certain parts of the body.

“This could provide a range of benefits, one of which could be to boost the pain-killing capabilities of drugs,” he said.

The research could lead to the development of numerous new medicines.

“Currently, there are many peptides and proteins that have the potential to be developed as new drugs,” Professor Toth said.

“However, a lack of oral absorption and poor in vivo stability are major hurdles that must first be overcome, before any of these peptides or proteins will reach the clinic.

“This research could provide the answer.”

The UQ research group is also working in conjunction with the Queensland Institute of Medical Research (QIMR) on a related project, which aims to make vaccinations orally deliverable.

The research could save millions of lives a year, by drastically reducing the cost of vaccines.

“This is of extreme importance to the developing world, where the costs of injectable medicines becomes prohibitive,” Professor Toth said.

“Oral medication would cost much less. The compounds used for the vaccination would be much more stable so drugs wouldn’t require refrigeration as they currently do, and people could simply take a tablet, rather than needing a medical professional to administer a vaccine.”

For more information, contact Professor Istvan Toth, telephone 3365 1386.