A Phase I trial reported a first-in-human proof of concept for KRAS-mutant vaccination to intercept pancreatic cancer development in high-risk patients. In Cancer Discovery, investigators reported safety and KRAS-specific T-cell responses in 90% of participants after vaccination. After a median follow-up of 16.5 months, none of the trial participants developed pancreatic cancer; the study also noted some shrinkage or stabilization of precancerous lesions. The approach targets common KRAS mutations, which drive more than 90% of pancreatic ductal adenocarcinoma cases. For the prevention and early-interception oncology space, the work provides an early signal that an immunization strategy could complement or enhance surveillance pathways used for hereditary or imaging-detected high-risk cohorts.