‘Real hope’ for cancer cure as personalised vaccines trialled

Doctors have begun trialling the first personalised mRNA cancer vaccines for melanoma in hundreds of patients as experts hailed its “gamechanging” potential to cure cancer.

Melanoma affects about 132,000 people a year and is the biggest skin cancer killer globally. Surgery is the main treatment, though radiotherapy, medicine and chemotherapy may be used. Now experts are testing jabs that are custom-built for each patient and tell their body to hunt down cancer cells to avoid a recurrence. A phase 2 trial found the vaccine dramatically improved survival and could stop cancer returning. Now a final phase 3 trial is being led by University College London Hospitals NHS trust.

Dr Heather Shaw, the national coordinating investigator for the trial, said the jabs had the potential to cure people with melanoma and were being tested in other cancers, including lung, bladder and kidney. “This is one of the most exciting things we’ve seen in a really long time,” said Shaw.

“This is a really finely honed tool. To be able to sit there and say to your patients that you’re offering them something that’s effectively like the Fat Duck at Bray versus McDonald’s – it’s that level of cordon bleu that’s coming to them.”

The vaccine is designed to trigger the immune system so it can fight back against a patient’s specific type of cancer. Known as mRNA-4157 (V940), it targets tumour neoantigens, markers on tumours that can potentially be recognised by the immune system. It carries coding for up to 34 neoantigens and activates an anti-tumour immune response based on the cancer’s unique mutations.

To create each jab, a sample of tumour is removed during surgery, followed by DNA sequencing and the use of artificial intelligence. The result is a custom-built anti-cancer jab specific to the patient’s tumour.

The ultimate aim is to cure patients permanently of their cancer. “I think there is a real hope that these will be the gamechangers in immunotherapy,” Shaw said.

Phase 2 data found people with serious high-risk melanomas who

had the jab alongside the immunotherapy Keytruda were almost half (49%) as likely to die or have their cancer come back after three years as those who were given only Keytruda.

Patients received one milligram of the mRNA vaccine every three weeks for up to nine doses and 200 milligrams of Keytruda every three weeks (maximum 18 doses) for about a year.

The phase 3 global trial will include a wider range of patients, and aims to recruit about 1,100 people. The UK arm will involve at least 60 to 70 patients in eight centres, including in London, Manchester, Edinburgh and Leeds. One of the first patients on the trial at UCLH is Steve Young, 52, from Stevenage in Hertfordshire. “I’m really, really excited,” he said. “This is my best chance at stopping the cancer in its tracks.”

‘This is a finely honed tool … It’s like the Fat Duck at Bray versus McDonald’s – it’s that level of cordon bleu’

Dr Heather Shaw National coordinator