A KRAS-targeted vaccine demonstrated early safety and immunogenicity in a first-in-human pancreatic cancer interception study, reported in Cancer Discovery. The peptide vaccine (mKRAS-VAX) targeting six common KRAS mutations was tested in high-risk participants with hereditary PDAC predisposition and a radiographic pancreatic abnormality. After a median follow-up of 16.5 months, no participants developed PDAC, while 90% generated mKRAS-specific T-cell responses and vaccine-induced clonotypes persisted for up to two years. The trial offers the first proof-of-concept signal for vaccination as an interception strategy in individuals undergoing surveillance for precursors.