Therapeutic Efficacy of a Bivalent Inhibitor of Prostate-Specific Membrane Antigen Labeled with 67Cu

J Nucl Med. 2021 Jun 1;62(6):829-832. doi: 10.2967/jnumed.120.251579. Epub 2020 Oct 16.

Abstract

Radionuclide therapy targeting prostate-specific membrane antigen (PSMA) is promising for prostate cancer. We previously reported a ligand, 64Cu-CuSarbisPSMA, featuring 2 lysine-ureido-glutamate groups. Here, we report the therapeutic potential of 67Cu-CuSarbisPSMA. Methods: Growth of PSMA-positive xenografts was evaluated after treatment with 67Cu-CuSarbisPSMA or 177Lu-LuPSMA imaging and therapy (I&T). Results: At 13 d after injection, tumor growth was similarly inhibited by the 2 tracers in a dose-dependent manner. Survival was comparable after single (30 MBq) or fractionated (2 × 15 MBq, 2 wk apart) administrations. Conclusion:67Cu-CuSarbisPSMA is efficacious in a PSMA-expressing model of prostate cancer.

Keywords: 64Cu; 67Cu; prostate cancer; prostate-specific membrane antigen; theranostics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Surface / chemistry*
  • Cell Line, Tumor
  • Cell Transformation, Neoplastic
  • Copper Radioisotopes / chemistry*
  • Glutamate Carboxypeptidase II / chemistry*
  • Isotope Labeling
  • Male
  • Prostatic Neoplasms / pathology

Substances

  • Antigens, Surface
  • Copper Radioisotopes
  • Copper-67
  • FOLH1 protein, human
  • Glutamate Carboxypeptidase II