To achieve an OC-directed blockade of the CD73/ADO immune checkpoint, we engineered a novel tetravalent bsAb, designated bsAb CD73xEpCAM, that selectively binds to the pan-carcinoma-associated cell surface antigen ‘Epithelial Cell Adhesion Molecule’ (EpCAM) and concurrently blocks CD73. Here, NT5E is linked to carcinoma.