The world’s first personalised mRNA cancer vaccine for melanoma halves the risk of patients dying or the disease returning, according to trial results that doctors described as “extremely impressive”.
Melanoma affects more than 150,000 people a year globally, according to 2020 figures from World Cancer Research Fund International.
Patients who received the vaccine after having a stage 3 or 4 melanoma removed had a 49% lower risk of dying or the disease recurring after three years, data presented at the world’s largest cancer conference showed. The NHS in the UK is among the organisations testing the jab.
A primary investigator on the study, oncologist Prof Georgina Long, said the average risk of recurrence after surgery for the cohort of advanced cancer patients was 50%.
“Although we do need to look at the five and 10-year numbers, most of the risk of recurrence in this group occurs in that first two years,” the 2024 Australian of the Year said.
The 157 patients in the phase 2b trial had high-risk melanomas and either had the jab, developed by Moderna and Merck, alongside the immunotherapy Keytruda or were given only Keytruda.
The vaccine and the Keytruda brought the risk of recurrence down to 25%, Long said. However, she cautioned the results were a “signal” with a larger trial needed to evaluate the true impact better.
The 2.5-year recurrence-free survival rate for the jab in combination with Keytruda was 74.8%, compared with 55.6% for Keytruda alone, delegates at the American Society of Clinical Oncology (ASCO) annual meeting in Chicago heard.
“We are encouraged by the latest results,” said Kyle Holen, Moderna’s head of development, therapeutics and oncology. “These findings reinforce our commitment to advancing this innovative treatment.”
Iain Foulkes, the executive director of research and innovation at Cancer Research UK, said the results marked another milestone in “the exciting, developing landscape of cancer vaccine research”.
“After three years of follow up, the data suggests that levels of cancer relapse did not increase in people with high-risk, advanced stage melanoma,” he said. “The findings highlight the great promise of therapeutic cancer vaccines used in combination with powerful immunotherapies.”
Known as mRNA-4157 (V940), the jab is custom-built for each patient and tells their body to kill any remaining cancer cells and prevent the disease ever coming back.
A sample of tumour is removed during the patient’s 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.
A second trial presented at ASCO, led by the University of Vienna, found cancer jabs can significantly improve survival for breast cancer patients after surgery.
The study involved 400 patients with early stage breast cancer. Half were given a vaccine to stimulate their immune system before surgery.
After seven years, 81% of patients who had the vaccine were still alive and free of breast cancer, compared with 65% of those who had received standard care.
The lead author, Dr Christian Singer, said: “This is the first significant and profound long-term survival benefit of an anti-cancer vaccine in breast cancer patients reported to date.”
Prof Charles Swanton, Cancer Research UK’s chief clinician, said the melanoma trial results were “extremely impressive”.
“It’s terribly exciting,” Swanton said. “The new vaccine approach is another piece of the puzzle that will allow more patients to be cured, hopefully, or fewer patients to suffer disease relapse. Ultimately it will contribute to survival rates improving continually over the next decades and more.”
Thousands of patients in England are being fast-tracked into groundbreaking trials of personalised cancer vaccines in a revolutionary world-first NHS “matchmaking” scheme to save lives.
