We live in a sunburnt country, but unfortunately that means Australia has one of the highest rates of melanoma in the world, with one person dying from the cancer every six hours.
Now, Australian scientists have led a world-first trial of a personalised cancer vaccine that cuts the risk of melanoma returning or death after surgery by almost half.
The breakthrough marks a major step forward in cancer treatment.
What did the trial find?
The Australian-led trial involved 1137 people across 157 sites worldwide. All had undergone surgery to remove their melanoma but were at high risk of it coming back.
Everyone received pembrolizumab, an immunotherapy drug also known as Keytruda, for a year. Two-thirds were also given the personalised vaccine, while the others received a placebo.
Adding the vaccine reduced the risk of melanoma returning or death by 42 per cent compared with immunotherapy alone.
After two years, 82 per cent of people who received both treatments were alive without their melanoma returning, compared with 70 per cent of those given immunotherapy alone.
The trial was led by Professor Georgina Long, medical director at Melanoma Institute Australia, who was named joint 2024 Australian of the Year alongside the late Richard Scolyer.
“These findings are a foundational shift in our approach to cancer: harnessing the immune system in a more personalised way to reduce the risk of melanoma recurrence or death,” she said.
“This has not been achieved before in the history of cancer drug development.”
How does a personalised cancer vaccine work?
Developed by Moderna and Merck, the intismeran vaccine uses mRNA technology to teach the immune system to recognise and attack cancer cells.
To make it, researchers analysed a sample of each patient’s tumour, looking for genetic changes that set it apart from healthy cells. They then used that information to create a vaccine specifically for that person’s cancer.
It works alongside pembrolizumab, which stops cancer cells from hiding from the immune system. The vaccine helps the immune system recognise those cells, while pembrolizumab helps it fight back.
When will it be available?
The vaccine isn’t yet available as a standard treatment in Australia. It will now go through regulatory review, which could take several years.
The results have been accepted for publication in the New England Journal of Medicine. Researchers will continue following participants to see whether the combination helps people live longer overall.
The landmark trial could have implications beyond melanoma, with the approach already being studied in other cancers, including lung cancer.
“Having succeeded in melanoma, this proof of concept could mark the beginning of a foundational shift in how we treat cancer, helping patients remain cancer-free for longer,” Professor Long said.
