ESR1-PRKN targeted vaccine

The ESR1-PRKN targeted vaccine is an investigational immunotherapeutic approach designed to combat therapy-resistant breast cancer. It leverages personalized peptide and mRNA vaccine strategies to target the ESR1-PRKN fusion protein, which is identified as a clinically relevant fusion generating immunogenic neoantigens. This fusion protein was discovered in patient-derived xenograft (PDX) models of ER+/HER2+ breast cancer with acquired resistance to CDK4/6 inhibitors. The vaccine aims to elicit a robust, HLA-A*01:01-specific T-cell immune response against these neoantigens, leading to clonal expansion of cytotoxic CD8+ T cells.