Australian researchers have designed a cancer treatment that doesn’t damage healthy tissue
Australian researchers have developed a brain cancer drug in a major breakthrough that could save thousands of lives. Here’s how
Illness
Don't miss out on the headlines from Illness. Followed categories will be added to My News.
Exclusive: Researchers have developed a brain cancer drug that can cut through the brain’s protective coating – the blood-brain barrier – in a major breakthrough that could save thousands of lives.
While the skull, for example, protects against physical damage, the blood – brain barrier provides a defence against disease-causing pathogens and toxins present in our blood.
But a new delivery method for brain cancer treatment that worked in mice and human clinical trials could begin at the end of this year.
Professor Kris Thurecht, from the ARC Centre of Excellence in Bio Nano Science, said the nanomedicine his team has developed not only gets into the tumour tissue, but also travels to the core of the tumour.
Around 1800 Australians are diagnosed with brain cancer every year but it has among the lowest survival rate of any cancer with just 4 per cent of people still alive five years.
One of the reasons is that the brain has a protective barrier of blood vessels that block most substances from the bloodstream, including medicines, entering the brain.
“It’s exquisite until you need to treat something in the brain,” Professor Thurecht said.
It means the main form of treatment for brain cancer is surgery which can damage the brain and which often fails to remove all the tumour.
Chemotherapy and radiotherapy are the next steps.
To overcome this defence mechanism in brain cancer patients Professor Thurecht has designed nanomedicines to shuttle the medicine into the brain.
A synthetic nanoparticle called polyetheylene glycol (PEG) is wrapped around a small dose of the medicine doctors wish to use.
The PEG acts like a lolly wrapper making the medicine invisible to the immune system allowing it to cross the blood-brain barrier.
Once in the brain tumour the high acid levels in cancer cells trigger the release of the drug from its wrapper.
Professor Thurecht’s latest research published in the American Chemical Society journal Central Science showed the nanoparticles pierced the blood-brain barrier in mice who had a common brain cancer called glioblastoma.
The drug then went to work destroying the tumour cells while leaving healthy cells untouched.
“Nanomedicines have been called guided missiles,” said Professor Thurecht.
In other preliminary and unpublished work, researchers have found the drugs slow the tumour growth in mice and they live longer than mice not treated with the drug.
Human trials at the Princess Alexandria Hospital in Brisbane were originally planned for the middle of this year but were delayed by the COVID-19 outbreak.
Professor Thurecht hopes the trials will now go ahead at the end of this year.
Initially the human trials will test whether the nanomedicine’s coating can pierce the human blood-brain barrier but no therapeutic agent will be used.
Later trials will place small amounts of drugs typically used to treat brain cancer (temozolomide and lomustine) into the nanomedicine to see if they are taken into the brain tumour.
“Our nanomedicines offer a route to delivery that can minimise side effects, as well as deliver newer drugs that may be too toxic to deliver in any other way,” Professor Thurecht said.
Last week US researchers reported they had successfully trialled a new vaccine to combat glioblastoma the most common and aggressive form of brain cancer.
The vaccine stimulates the body’s own immune system to fight the tumour.
It is created using a patient’s own tumour cells, extracted at the time of surgery.
These tumour cells are treated with a compound that targets a receptor known to drive tumour growth and this is then irradiated and implanted back into the patient’s abdomen to act as a vaccine.
Patients on the highest dose of the vaccine survived for an average of 21.9 months, compared to 14.6 months on standard therapy.