Anti-KLK2 / Kallikrein 2 is a radioimmunoconjugate containing h11B6, a humanized immunoglobulin G1 (IgG1) monoclonal antibody that targets human kallikrein-2 (hK2), conjugated with the bifunctional, macrocyclic chelating agent tetra-azacyclododecanetetra-acetic acid (DOTA), and labeled with the alpha-emitting radioisotope actinium Ac 225, with potential antineoplastic activity. MW: 145.5 kD.