Beyond Neoantigens: Antigens Derived from Tumor Drivers as Cancer Vaccine Targets.

A vaccine targeting HER2, a non-mutated but overexpressed tumor antigen, readily primed T-cells for ex vivo expansion and adoptive transfer with minimal toxicity. This regimen led to intramolecular epitope spreading in a majority of patients and offers a treatment modality that may improve outcomes for patients with metastatic breast cancer expressing HER2.