Researchers at Johns Hopkins reported Phase 1 results for a peptide-based pancreatic cancer vaccine targeting the most common mutant KRAS variants in high-risk individuals. Published in Cancer Discovery, the study described induced protective, antigen-specific T cell responses and a signal of slowed progression from pancreatic lesions toward pancreatic cancer. The trial enrolled 20 participants with genetic predisposition to pancreatic ductal adenocarcinoma and confirmed pancreatic lesions that had not progressed to cancer. The team administered a KRAS peptide vaccine at four immunization timepoints, including a booster four weeks after the final prime, and monitored immune responses via peripheral blood mononuclear cells. Participants reported only mild side effects that resolved on their own, supporting continued development in larger trials as the study team frames this as early evidence of immune activation.