[211At]At-girentuximab

[211At]At-girentuximab (ATO-101) is an investigational targeted alpha radiopharmaceutical comprising the chimeric anti–carbonic anhydrase IX (CAIX) IgG1 monoclonal antibody girentuximab labeled with the alpha‑emitting radionuclide astatine-211, being developed primarily for intravesical treatment of non–muscle-invasive bladder cancer (NMIBC) that is unresponsive to standard therapy.[3][1][5][6][11] Girentuximab (also known as cG250, Rencarex, TLX250) binds with high affinity to CAIX, a hypoxia-associated cell surface enzyme highly expressed on clear cell renal cell carcinoma and other CAIX‑positive tumors, enabling selective delivery of localized alpha radiation to malignant cells while sparing most normal tissues.[2][3][4][6][11] In preclinical studies using CAIX-positive bladder cancer models, [211At]At-girentuximab demonstrated high binding affinity, significant cytotoxicity relative to 177Lu-girentuximab, and favorable biodistribution with low systemic uptake following intravesical administration, supporting its development as a first-in-human targeted alpha therapy for NMIBC.[3][5] The construct leverages the established CAIX-targeting biology of girentuximab, originally developed by Wilex and now licensed by Telix Pharmaceuticals for radioimmunoconjugate applications, while substituting an alpha-emitting isotope (211At) to induce potent, short-range DNA damage within CAIX-expressing tumor cells in the bladder wall.[3][5][6][7]

Brand names

ATO-101ATO101ATO 101

Other names

211At-astatine-girentuximab211At-girentuximab211At-anti-CA-IX antibody211At-anti-CAIX antibodyATO-101ATO101ATO 101