NBC News reports on a 16-person clinical trial of "personalized messenger RNA vaccines" which use the immune system to fight cancer cells. "The goal is not to eliminate existing tumors, but instead to stamp out lingering, undetected cancer cells, and later any new cells that form before they can cause a recurrence."Patients still have surgery to remove tumors. After that, the mRNA vaccines are personalized for each individual using genetic material taken from their unique tumor cells. In the clinical trial, after getting the vaccine, the patients also received chemotherapy, which is standard post-op treatment for operable pancreatic cancer... [The article notes that less than 13% of people diagnosed with pancreatic cancer live for more than five years, making it "one of the deadliest cancers."] [E]xperts have long believed that people with pancreatic cancer could not generate an immune response against tumors. But after nine doses of the personalized vaccine, [clinical trial participant Donna] Gustafson is one of eight people in the 16-person Phase 1 trial who did just that, producing an army of immune cells called T cells that seek out and destroy tumor cells... [Dr. Vinod Balachandran, a vaccine center director who is leading the trial, said] it was unclear whether the immune response would last and lead to the patients living longer... New data collected during the trial's six-year follow-up period shows that it may. Those findings will be presented Monday at the American Association for Cancer Research's annual meeting in San Diego. Six years after treatment, Gustafson and six others who responded to the treatment are still alive... More research is still needed. Genentech and BioNTech, the two drugmakers behind the vaccine, have already launched a larger Phase 2 clinical trial... Another team is working on an off-the-shelf vaccine that targets a protein called KRAS that is present in as many as 90% of pancreatic cancers. In a small, early trial, about 85% of the participants mounted an immune response to the protein.Read more of this story at Slashdot.