Patient-specific tumor neoantigens (personalized, up to 34 per patient)

Class

mRNA-based individualized neoantigen therapy (personalized cancer vaccine)

Pathway

Antigen presentation / adaptive immunity, typically combined with anti-PD-1 checkpoint blockade

Tumor cells accumulate somatic mutations during cancer development, and some of these mutations alter protein sequences in ways that create peptides absent from healthy tissue. These altered peptides, called neoantigens, are displayed on the tumor cell surface bound to major histocompatibility complex (MHC) molecules, marking the cell as foreign to the immune system. Because each tumor carries a distinct set of mutations, most neoantigens are unique to a single patient rather than shared across a disease type. A personalized neoantigen vaccine addresses this by first sequencing a patient's tumor and healthy tissue to identify tumor-specific mutations, then using computational prediction to select which resulting peptides are most likely to bind that patient's own HLA proteins and be recognized by T cells. A panel of up to several dozen such peptides is encoded in messenger RNA and manufactured as an individualized vaccine, intended to train the immune system to recognize and destroy tumor cells bearing those mutations. This approach is relevant across cancers with sufficient mutational burden to yield workable neoantigen candidates, and it is typically deployed alongside anti-PD-1 checkpoint blockade, which removes an inhibitory signal that would otherwise blunt the antitumor T-cell response the vaccine generates.