Definition

A bispecific antibody that targets both the tumor-associated antigen (TAA) human prostate-specific membrane antigen (PSMA) and the CD3 antigen found on T lymphocytes, with potential immunostimulatory and antineoplastic activities. Upon administration of anti-PSMA/CD3 bispecific antibody REGN4336, this bispecific antibody binds to both CD3 on cytotoxic T lymphocytes (CTLs) and PSMA found on PSMA-expressing tumor cells. This activates and redirects CTLs to PSMA-expressing tumor cells, which results in the CTL-mediated cell death of PSMA-expressing tumor cells. PSMA is overexpressed on the surface of metastatic and hormone-refractory prostate cancer cells.