Preclinical PET imaging of bispecific antibody ERY974 targeting CD3 and glypican 3 reveals that tumor uptake correlates to T cell infiltrate

J Immunother Cancer. 2020 Mar;8(1):e000548. doi: 10.1136/jitc-2020-000548.

Abstract

Background: Bispecific antibodies redirecting T cells to the tumor obtain increasing interest as potential cancer immunotherapy. ERY974, a full-length bispecific antibody targeting CD3ε on T cells and glypican 3 (GPC3) on tumors, has been in clinical development However, information on the influence of T cells on biodistribution of bispecific antibodies, like ERY974, is scarce. Here, we report the biodistribution and tumor targeting of zirconium-89 (89Zr) labeled ERY974 in mouse models using immuno-positron emission tomography (PET) imaging.

Methods: To study both the role of GPC3 and CD3 on the biodistribution of [89Zr]Zr-N-suc-Df-ERY974, 89Zr-labeled control antibodies targeting CD3 and non-mammalian protein keyhole limpet hemocyanin (KLH) or KLH only were used. GPC3 dependent tumor targeting of [89Zr]Zr-N-suc-Df-ERY974 was tested in xenograft models with different levels of GPC3 expression. In addition, CD3 influence on biodistribution of [89Zr]Zr-N-suc-Df-ERY974 was evaluated by comparing biodistribution between tumor-bearing immunodeficient mice and mice reconstituted with human immune cells using microPET imaging and ex vivo biodistribution. Ex vivo autoradiography was used to study deep tissue distribution.

Results: In tumor-bearing immunodeficient mice, [89Zr]Zr-N-suc-Df-ERY974 tumor uptake was GPC3 dependent and specific over [89Zr]Zr-N-suc-Df-KLH/CD3 and [89Zr]Zr-N-suc-Df-KLH/KLH. In mice engrafted with human immune cells, [89Zr]Zr-N-suc-Df-ERY974 specific tumor uptake was higher than in immunodeficient mice. Ex vivo autoradiography demonstrated a preferential distribution of [89Zr]Zr-N-suc-Df-ERY974 to T cell rich tumor tissue. Next to tumor, highest specific [89Zr]Zr-N-suc-Df-ERY974 uptake was observed in spleen and lymph nodes.

Conclusion: [89Zr]Zr-N-suc-Df-ERY974 can potentially be used to study ERY974 biodistribution in patients to support drug development.

Keywords: T-lymphocytes; antibodies, neoplasm; immunotherapy; lymphocyte activation; translational medical research.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Bispecific / pharmacology*
  • Antibodies, Bispecific / therapeutic use
  • Antineoplastic Agents, Immunological / pharmacology*
  • Antineoplastic Agents, Immunological / therapeutic use
  • Apoptosis
  • CD3 Complex / immunology*
  • Carcinoma, Hepatocellular / diagnostic imaging
  • Carcinoma, Hepatocellular / drug therapy*
  • Carcinoma, Hepatocellular / immunology
  • Carcinoma, Hepatocellular / pathology
  • Cell Proliferation
  • Female
  • Glypicans / immunology*
  • Humans
  • Liver Neoplasms / diagnostic imaging
  • Liver Neoplasms / drug therapy
  • Liver Neoplasms / immunology
  • Liver Neoplasms / pathology
  • Lymphocytes, Tumor-Infiltrating / immunology*
  • Mice
  • Mice, Inbred NOD
  • Mice, SCID
  • Positron-Emission Tomography / methods*
  • Radioisotopes / chemistry
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / immunology
  • Tumor Cells, Cultured
  • Xenograft Model Antitumor Assays
  • Zirconium / chemistry

Substances

  • Antibodies, Bispecific
  • Antineoplastic Agents, Immunological
  • CD3 Complex
  • GPC3 protein, human
  • Glypicans
  • Radioisotopes
  • bispecific antibody ERY974
  • Zirconium
  • Zirconium-89