In a major breakthrough for preventative medicine, the University of Oxford and pharmaceutical giant Moderna have developed a first-of-its-kind vaccine aimed at preventing bowel, ovarian, and other cancers in individuals at high genetic risk.
A clinical trial launching this summer will evaluate whether the investigational mRNA jab can train the immune system to identify and destroy pre-cancerous cells before tumours can form. The move marks Moderna's first foray into utilising its messenger RNA (mRNA) technology for cancer prevention rather than treatment.
Targeting Lynch Syndrome
The upcoming 'Intercept-Lynch' trial specifically targets individuals with Lynch syndrome, a genetic condition that causes a lifelong, heightened vulnerability to multiple malignancies. An estimated 1 in 300 people in England, roughly 175,000 individuals, live with Lynch syndrome, yet a staggering 95% are unaware they carry the faulty gene. The condition alters a gene responsible for repairing damaged DNA, causing mutations to accumulate rapidly.
'People with Lynch syndrome are at risk of cancers over their entire lives,' explained Professor David Church, the trial's lead investigator and a Cancer Research UK fellow at Oxford. '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. 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.'
High Stakes for Patients
The stakes for these patients are exceptionally high. Around 1,100 bowel cancers are caused by Lynch syndrome each year in England, and it is thought the syndrome increases the lifetime risk of developing the disease by around 80%. The condition also sharply drives up the risk of womb, ovarian, stomach, pancreatic, kidney, and skin cancers.
The new vaccine, designated mRNA-4194, functions essentially as a biological 'instruction manual'. While the genetic mutations caused by Lynch syndrome typically hide from the body's natural defences, the vaccine forces these abnormalities to become visible to the immune system. With the right stimulation, the body can actively attack and eliminate the abnormal cells before they turn malignant.
Broad Protection Potential
Because the vaccine targets traits shared across various tumour types, researchers believe it could provide broad, multi-organ protection. It is designed both for people who have never had cancer and for Lynch syndrome patients who have already survived a primary diagnosis.
Backed by Cancer Research UK, the initial phase of the trial will focus on analysing patient immune responses, determining optimal dosing, and establishing safety profiles. A second, expanded phase involving multiple centres across the UK is projected to begin in 2027.
Implications Beyond Lynch Syndrome
Experts emphasise that the implications of the study stretch far beyond Lynch syndrome. If successful, the trial will provide a crucial 'proof of principle' that the immune system can be pre-emptively trained to stop cancer in its tracks, a blueprint that could eventually be adapted to protect the wider public from other forms of the disease.
'By applying mRNA technology earlier in the patient journey, we aim to harness the immune system when it can have the greatest impact,' said David Berman, Chief Development Officer at Moderna, noting that the company is proud to advance the innovative research alongside leading British institutions.
