Treatment of Metastatic Renal Cell Carcinoma With CAIX CAR-engineered T Cells: Clinical Evaluation and Management of On-Target Toxicity

Mol Ther. 2013 Apr;21(4):904-12. doi: 10.1038/mt.2013.17. Epub 2013 Feb 19.

Abstract

Autologous T cells genetically modified to express a chimeric antibody receptor (CAR) against carboxy-anhydrase-IX (CAIX) were administered to 12 patients with CAIX-expressing metastatic renal cell carcinoma (RCC). Patients were treated in three cohorts with a maximum of 10 infusions of a total of 0.2 to 2.1 × 10(9) CAR T cells. CTC grade 2-4 liver enzyme disturbances occurred at the lowest CAR T cell doses, necessitating cessation of treatment in four out of eight patients in cohorts 1 and 2. Examination of liver biopsies revealed CAIX expression on bile duct epithelium with infiltration of T cells, including CAR T cells. Subsequently four patients were pre-treated with CAIX monoclonal antibody (mAb) G250 to prevent CAR-specific toxicity and showed no liver toxicities and indications for enhanced peripheral T cell persistence. No clinical responses were recorded. This report shows that CAIX-targeting CAR T cells exerted antigen-specific effects in vivo and induced liver toxicity at the lowest dose of 0.2 × 10(9) T cells applied, illustrating the potency of receptor-modified T cells. We provide in-patient proof that the observed "on-target" toxicity is antigen-directed and can be prevented by blocking antigenic sites in off-tumor organs and allowing higher T cell doses.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbonic Anhydrases / metabolism
  • Carcinoma, Renal Cell / drug therapy*
  • Carcinoma, Renal Cell / immunology*
  • Cytokines / metabolism
  • Flow Cytometry
  • Gene Dosage / genetics
  • Humans
  • Immunohistochemistry
  • Kidney Neoplasms / drug therapy*
  • Kidney Neoplasms / immunology*
  • T-Lymphocytes / immunology*
  • Treatment Outcome

Substances

  • Cytokines
  • Carbonic Anhydrases