Cancer Vaccines

Therapeutic cancer vaccines train the immune system to recognize antigens — molecules present on cancer cells but scarce or absent in healthy tissue — and to destroy the cells that carry them. Formally they are a branch of immunotherapy; we present them as a separate group because the field has gained clear momentum, capped in August 2026 by the first positive phase 3 trial of an individualized neoantigen therapy. Unlike preventive vaccines, which protect healthy people against infections that can lead to cancer, treatment vaccines are given to people who already have the disease. The group spans very different approaches: BCG, a bacterial preparation used in bladder cancer for decades; sipuleucel-T, a cellular vaccine for prostate cancer; and personalized mRNA vaccines designed from the mutations of an individual patient's tumor.