Clinicians at Lausanne University Hospital and the Ludwig Institute for Cancer Research described a proof-of-concept personalized neoantigen vaccine in aggressive ovarian cancer that generated a durable immune response while acting as a “living lab” for identifying tumor-reactive T-cell receptors. The report highlights how sequencing-driven vaccine design can be coupled with deep immune profiling to pinpoint which TCRs respond. The work also supports a practical workflow for TCR discovery from patient immune activity, potentially accelerating the selection of biomarkers and adoptive cellular targets. While early, the findings provide a concrete demonstration of translational coupling between neoantigen selection and functional T-cell readouts.