Researchers at Johns Hopkins University reported Phase 1 results indicating that a peptide-based vaccine targeting six common mutant KRAS variations can generate protective, antigen-specific T-cell responses in high-risk individuals and slow progression of pancreatic lesions. The findings were published in Cancer Discovery. In the trial, 20 participants with genetic predisposition to pancreatic ductal adenocarcinoma and confirmed pre-cancerous lesions received a series of four immunizations, including a booster dose four weeks after the final prime. Peripheral blood samples were collected repeatedly to quantify immune responses, with reported side effects limited to mild, self-resolving events. The study also reported a median immune-response metric post-vaccination and described a lesion progression slowdown relative to baseline trajectories, supporting continued evaluation in larger efficacy-focused trials. The work builds on prior safety and immunogenicity observations conducted when participants were receiving monoclonal antibody therapy or following surgery and treatment.