Source : Perth Now news
Australia is at the centre of a major melanoma breakthrough, with 2024 Australian of the Year Professor Georgina Long leading a global trial that could reshape treatment after surgery for people at high risk of the cancer returning.
A personalised mRNA therapy from Moderna and Merck, used with the immunotherapy drug pembrolizumab, has delivered the first positive result in a late-stage clinical trial for an mRNA cancer treatment.
The trial involved patients with high-risk melanoma after their tumours had been completely removed.
Professor Long, joint-recipient of the 2024 Australian of the Year Award with Professor Richard Scolyer, was the trial’s principal investigator and is medical director of Melanoma Institute Australia.
She said the findings were a “meaningful step forward” for patients living with the fear that melanoma could return even after surgery.
“Even after surgery to remove a melanoma when it has spread to lymph nodes and distant parts of the body, there is always a risk that the cancer can return,” Professor Long told NewsWire.
“These results show that adding intismeran to pembrolizumab, a type of immunotherapy, significantly reduces the risk of the cancer coming back compared to pembrolizumab alone.
“For patients with high-risk melanoma, that is a meaningful step forward.”
The global trial found the combination of intismeran autogene and pembrolizumab helped keep melanoma from returning and reduced the risk of it spreading to distant parts of the body.
The study enrolled 1137 patients with stage IIB, IIC, III or IV cutaneous melanoma who had already had their tumours removed and had not received previous systemic treatment.
Participants were randomly assigned to receive either the personalised mRNA treatment plus pembrolizumab, or pembrolizumab on its own, over about a year.
Professor Long said the treatment is made for each patient individually, using a sample of their tumour to map its unique mutations before creating an mRNA therapy designed to help the immune system recognise and attack those cancer cells.
“Unlike a traditional vaccine that prevents disease in healthy people, this is a therapeutic vaccine, meaning it is designed for people who already have cancer, to help stop the cancer coming back,” she said.
She said the result was important not only for melanoma, but for cancer treatment more broadly, because it showed for the first time in a late-stage trial that an mRNA therapy could be designed around an individual patient’s cancer and make a meaningful difference to outcomes.
The findings carry particular significance in Australia, where melanoma rates are among the highest in the world.
“More Australians are diagnosed with melanoma each year than almost anywhere else, and it remains one of the most common causes of cancer death in younger Australians,” Professor Long said.
“Any treatment that reduces the risk of recurrence after surgery has the potential to affect a very large number of people here.”
No new safety concerns were found, and the trial will keep following patients, including whether the treatment helps them live longer.
Professor Long said the result was especially encouraging because it was the first time an mRNA-based cancer treatment had shown benefit in a late-stage trial, and the first late-stage result for any individualised neoantigen therapy.
She said it was particularly encouraging that the combination met both the main goal of the trial and a key secondary measure, reducing the risk of the cancer returning and of it spreading to distant sites.
The result builds on earlier phase 2b data that had already pointed to strong promise for the approach.
At this year’s American Society of Clinical Oncology annual meeting, researchers reported five-year follow-up showing the combination cut the risk of recurrence or death by 49 per cent and cut the risk of distant metastasis or death by 59 per cent compared with pembrolizumab alone.
Professor Long told NewsWire she will present the full results at the European Society for Medical Oncology Congress in October.
“Merck and Moderna will then submit the data to regulatory authorities, including Australia’s Therapeutic Goods Administration, for review,” she said.
“That process can take anywhere between 12 and 24 months. If approved, a separate Pharmaceutical Benefits Scheme review would follow before the treatment becomes publicly subsidised in Australia.
“We are encouraged by today’s results, but there are important steps still to come.”
