Vaccine’s dual win Cancer treatment second-string hope
A VACCINE that treats one of the most common forms of breast cancer could one day also be used to prevent another form of the disease.
The therapy being developed by an Australian company stimulates the body’s own immune system to fight the cancer, and studies have produced improved survival rates in mice.
The vaccine will help the one in four women whose breast cancer overexpresses the HER2 protein as well as HER2 gastric cancer patients.
Over one million cases of gastric cancer are diagnosed each year, mostly in Asia, and the five-year survival rate is just 30 per cent.
European trials have shown the vaccine to be safe, and it is now being trialled in Asia on gastric cancer patients.
While researchers hope it will help breast cancer patients, they can’t trial it on these patients in Australia yet.
This is because standard use of the expensive drug Herceptin treatment here would conflict with proving the vaccine works.
Medical University of Vienna researcher Professor Ursula Wiedermann is the co-inventor of the HER-vaxx.
If it works it will most likely be used in combination with chemotherapy, radiation and Herceptin to improve survival, she said.
The idea is patients with newly diagnosed HER2 positive cancers would get the vaccine before receiving other treatments.
It would stimulate the body’s immune system to fight the cancer, before other standard treatments are loaded on top to kill it off.
Repeat vaccinations would most likely be needed during the patients’ lifetime.
“It’s like tetanus, you need a booster vaccine to keep the memory of the immune system activated,” Professor Wiedermann said.
Eventually the vaccine could be used to try and prevent cancer, she said.
“If you had a certain gene and your risk of cancer was high, it would make sense to prophylactically vaccinate (vaccines that stimulate an immune response),” she said.
Trials in mice showed the vaccine prolonged the onset of cancerous tumours and once a tumour was established it slowed tumour growth.
Australian company Imugene, based in Carlton South, is providing funding to develop the vaccine and run early trials.
Another vaccine against breast cancer developed by researchers at the Burnett Institute in Melbourne targeted the mucin 1 protein and slashed the rate of breast cancer returning from 60 to just 12 per cent in a 15-year period.
But work on that vaccine has stalled because of high costs when only a small number of women got an extension to their lifespan.