Scientists have been working on a revolutionary vaccine that could prevent certain people from developing bowel and ovarian cancer.
A trial is set to launch this summer to assess whether the jab can train the immune system to recognise and eliminate pre–cancerous cells in people with Lynch syndrome before cancer develops.
Around 175,000 people in England suffer from Lynch syndrome but only 5 per cent – equivalent to around 10,000 people – know they have it.
The inherited condition increases the risk of developing bowel cancer by 80 per cent. Around 1,100 bowel cancer cases are caused by the syndrome every year.
Lynch syndrome is linked to a far higher risk of bowel, womb and ovarian cancer, alongside other types such as stomach, pancreatic, kidney and skin cancer.
While the syndrome does not directly cause cancer, the genetic changes can lead to more abnormal cells developing, which then multiply and increase the risk of developing cancers, such as bowel, prostate and endometrial.
It is caused by an alteration in a gene called a mismatch repair gene. Carriers do not have any symptoms.
The new Intercept–Lynch trial is part of a scientific collaboration between the University of Oxford and Moderna, while Cancer Research UK has backed the vaccine development.
A trial is set to launch this summer to assess whether the jab can train the immune system to recognise and eliminate pre–cancerous cells in people with Lynch syndrome before cancer develops
Once patients receive the new mRNA–4194 jab, experts will then analyse their immune responses, assess what the perfect dose is and will check if the jab is safe.
The second phase of the study will include multiple centres across the UK, including Oxford, and is expected to begin in 2027.
The aim of the new trial is to ‘train the immune system with a vaccine’ to recognise abnormalities and stop them developing into cancer.
‘People with Lynch syndrome are at risk of cancers over their entire lives,’ says Professor David Church, Cancer Research UK senior cancer research fellow in the University of Oxford’s centre for human genetics and the lead investigator of the trial.
‘So, it’s very common, for instance, a woman to have a first cancer of her womb, and then some years later have a bowel cancer, or vice versa.
‘The targets we’ve chosen for the vaccine were chosen based on their sharedness across multiple cancer types in Lynch syndrome, so we think they should provide broad protection, if the vaccine works.’
In people with Lynch syndrome, mutations can build up, making the cells containing them more likely to transform into cancerous cells.
However, the mutations can be made visible to the immune system and, with enough stimulation, the immune system can attack the abnormal cells and stop cancer from forming.
Prof Church said the mRNA jab therefore acts as ‘an instruction manual’ for the body to attack the pre–cancerous cells.
He added that, as with many vaccines, there may be a need for patients to have a booster jab at some stage.
Regarding vaccinating against other cancers not caused by Lynch syndrome, Prof Church said ‘in terms of proof of principle that we can train the immune system to recognise these cancer–associated alterations and enhance the immune response against them to prevent these pre–cancers or prevent the progression of pre–cancer to cancer, that proof of principle should give us insights that are generalisable.’
David Berman, chief development officer at Moderna, said: ‘By applying mRNA technology earlier in the patient journey, we aim to harness the immune system when it can have the greatest impact.
‘We are proud to bring this innovation to the UK, building on our long–standing collaboration with leading UK institutions to advance mRNA research and development.’
