Experimental mRNA vaccines shrouded in controversy may protect against one of America’s deadliest cancers, a new study suggests. 

Researchers across the country tested a personalized mRNA vaccine on people with pancreatic cancer who had already had surgery and still had traces of the disease remaining. 

Pancreatic cancer is one of the hardest forms of the disease to treat, with a five-year survival rate of just 12 percent.

And most cases are diagnosed after the disease has ravaged other organs, as it symptoms are usually mistaken for more benign issues. 

The vaccine uses mRNA technology, which uses RNA to tell cells how to make proteins and induce an immune reaction, to targets mutations of the KRAS gene.

KRAS mutations are thought to be responsible for nine in 10 pancreatic cancers and nearly half of colon cancers. 

The researchers, from major institutions like Memorial Sloan Kettering Cancer Center in New York City and the University of California, Los Angeles (UCLA), found about 85 percent of participants had an immune response to the vaccine. And two-thirds had enough of a response to stave off lingering cancer cells. 

Participants also lived more than twice as long after getting the vaccine than pancreatic cancer patients on average. 

An mRNA vaccine has been shown to stave off pancreatic cancer (stock image)

Robert F Kennedy Jr has led the charge to cut down on vaccine research, including contracts looking into mRNA vaccines 

Dr Zev Wainberg, trial leader and co-director of the UCLA gastrointestinal oncology program, told NBC News: ‘That far exceeds the rates with resectable cancers.’

Resectable cancers are those than can be removed with surgery. 

mRNA technology, which is also used in Covid vaccines, has been hailed a ‘game-changer’ in the cancer space, leading to a mountain of new trials testing if it can be used in vaccines. 

In one research paper out of Penn State College of Medicine, the scientists note: ‘mRNA vaccines are an attractive and powerful immunotherapeutic platform against cancer because of their high potency, specificity, versatility, rapid and large-scale development capability, low-cost manufacturing potential, and safety.’ 

Despite expert consensus and scientific evidence, however, Health Secretary Robert F Kennedy Jr, a longtime vaccine skeptic, has repeatedly cast doubt on the safety and efficacy of mRNA vaccines. 

Earlier this month he announced the Department of Health and Human Services (HHS) would cancel nearly $500million in contracts for new vaccine development, including those for mRNA shots. 

Pancreatic cancer affects roughly 67,000 Americans every year and kills about 52,000. Along with colon cancer, it is also increasingly affecting young people. 

More than half the time, the disease is first spotted after it has already reached stage three or four due to its vague symptoms. These include abdominal pain, weight loss, back pain, jaundice and floating or clay-colored stools. 

This leads patients to assume their symptoms are from more benign causes like irritable bowel syndrome (IBS). 

By the time it reaches stage four, the five-year survival rate is just three percent, making it virtually incurable. 

The above chart shows the survival rate of pancreatic cancer by stage

Early signs of pancreatic cancer include jaundice, stomach pain, back pain and floating stools

It’s unclear exactly what causes pancreatic cancer, but smoking, obesity and diabetes are thought to increase the risk by inducing harmful inflammation that causes cells to divide and become mutated more easily. 

In the new phase I trial, published Monday in the journal Nature Medicine, doctors recruited 20 people with pancreatic cancer and five with colorectal cancer. 

All participants had a KRAS mutation and had undergone standard treatment, which usually includes chemotherapy and surgery, to shrink and remove most of their tumors. 

Blood tests revealed the patients had traces of cells left behind, known as microscopic residual disease, which can travel elsewhere in the body and grow into tumors. 

After surgery, each participant received up to six doses of the vaccine, called ELI-002 2P, and 13 also received booster shots. 

The team found 85 percent, or 21 out of 25 participants, showed an immune response to the vaccine, and about 66 percent had enough of an immune response to stave off lingering cancer cells.

And in nearly 70 percent of participants, the vaccine triggered an immune response not just to KRAS mutations but to other tumor cell targets not in the vaccine. 

The phase 1 trial also showed people with pancreatic cancer survived for an average of 29 months and lived recurrence-free for 15 months.

The average survival length for patients with stage four pancreatic cancer, which is when most are diagnosed, is usually just six months to a year. 

The team is now running a phase 2 trial to test the vaccine’s durability and compare if it is more effective than the current standard of care, which involves monitoring for disease recurrence.