Australian melanoma expert Georgina Long leads breakthrough phase 3 trial of personalised mRNA treatment

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.