First Personalised Cancer Vaccine Stops Disease Returning in Major Trial

Scientists have developed a new personalised cancer vaccine that could change how skin cancer is treated. When given alongside an existing medicine, the vaccine cut the risk of skin cancer returning or causing death by 42% in a large clinical trial. The trial involved more than 1,100 patients and took place over two years. Researchers say the results could be a major turning point in the fight against cancer.

The vaccine is called Intismeran and uses the same mRNA technology that was used in some COVID-19 vaccines. What makes it special is that it is built differently for every single patient. Doctors study the genes inside a patient's tumour and use that information to train the immune system to find and attack cancer cells if they return. This is what scientists mean when they talk about 'personalised medicine.'

The trial focused on adults who had already had their melanoma removed through surgery. Melanoma is a serious type of skin cancer that can spread to other parts of the body. In the study, 1,137 adults received Keytruda, a drug that helps the immune system fight cancer. About two-thirds of them also got Intismeran, while the rest received a placebo — a dummy treatment with no active medicine — so researchers could fairly compare the results.

After two years, patients who received the vaccine were much less likely to have their cancer come back or spread. The results showed the vaccine reduced the risk of melanoma spreading by 38% over two years. Drug companies MSD and Moderna, which created the vaccine, are already testing a similar approach on kidney, bladder, and lung cancers. Both companies said they may apply for approval from medicine regulators as early as next year.

One patient in the trial was Tony Chapman, a 75-year-old who was first diagnosed with melanoma in 2019. He had his tumour removed from his chest, but cancer later appeared under his arm, meaning it had returned and he needed a second operation. Tony then chose to join the trial because he wanted to help move science forward. Three years later, he has check-ups every six months and remains cancer-free.

Professor Pippa Corrie, a cancer specialist who helped run part of the study at Addenbrooke's Hospital in Cambridge, called the technology exciting and said the trial was the first real proof the idea works. Other independent experts also praised the results but said longer studies are still needed. Professor Alan Melcher of the Institute of Cancer Research in London described the results as 'very impressive' but warned that scientists should not assume the approach will automatically work for all types of cancer. He said longer follow-up research will be important to understand the full effect on how long patients live.

Even if the vaccine is approved, there are still big questions about cost. Each vaccine must be custom-made by genetically analysing a patient's tumour, which takes time and significant resources. Whether it becomes widely available on the NHS will depend on whether it is affordable for the health system. The trial will continue so that researchers can keep monitoring patients and learn more about the vaccine's long-term effects.