454A12-rRTA

454A12-rRTA is an investigational immunotoxin comprising the monoclonal antibody 454A12 conjugated to a recombinant version of the ricin A chain (rRTA). Developed through collaboration between the National Cancer Institute and the University of Texas Health Science Center, this agent specifically targets the transferrin receptor (TfR), a protein frequently overexpressed on the surface of rapidly dividing malignant cells due to their high iron requirements. Upon binding to the TfR, the immunotoxin is internalized into the cell via receptor-mediated endocytosis. Once inside the cytosol, the ricin A chain acts as a potent ribosome-inactivating protein (RIP) that halts protein synthesis by depurinating the 28S ribosomal RNA, ultimately leading to cell death. The drug has been evaluated in clinical trials for central nervous system malignancies, including leptomeningeal neoplasia and glioblastoma, and has demonstrated selective cytotoxicity against colon and pancreatic adenocarcinoma cells in laboratory studies.

Other names

454A12-ricin A chain immunotoxin454A12 recombinant ricin A chainanti-transferrin receptor immunotoxin