The population studied is small and specific: adults with a hereditary predisposition to pancreatic ductal adenocarcinoma who also had a pancreatic abnormality visible on imaging, typically a small cyst. For families that fit that description, and who have often watched a parent or sibling die of this disease, the result is meaningful news. For everyone else, it is early science.
What the trial did not do is show that the vaccine prevents cancer. Its endpoints were safety, immunogenicity, and T-cell persistence, and 20 participants followed for a median of 16.5 months cannot answer a prevention question.
