recombinant vaccinia-prostate-specific antigen vaccine

The recombinant vaccinia-prostate-specific antigen vaccine is a cancer immunotherapy consisting of a live-attenuated, recombinant vaccinia virus (poxvirus) vector engineered to express the human prostate-specific antigen (PSA) gene. Originally developed by the National Cancer Institute (NCI), the vaccine is designed to break immune tolerance to PSA, which is typically overexpressed in malignant prostate tissue. When administered, the viral vector infects host cells (primarily at the injection site), leading to the intracellular production and presentation of the PSA antigen. This process triggers a targeted immune response, specifically activating cytotoxic T lymphocytes (CTLs) to recognize and lyse PSA-expressing tumor cells. This construct served as the foundational component of the 'prime-boost' strategy in the PROSTVAC regimen, although later iterations (such as PROSTVAC-V) were enhanced with a triad of costimulatory molecules (TRICOM). Clinical development focused on patients with metastatic castration-resistant prostate cancer, but the program was largely halted after a Phase 3 study (PROSPECT) failed to meet its primary overall survival endpoint.

Other names

vaccinia-PSA vaccinerecombinant vaccinia-PSA vaccine