90Y-DOTA-Nimotuzumab: Synthesis of a Promising β- Radiopharmaceutical

Curr Radiopharm. 2022;15(1):32-39. doi: 10.2174/1874471013999210104220031.

Abstract

Background: Nimotuzumab is a humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody, nowadays used for tumour immunochemotherapy. This study aimed to label the conjugate DOTA-nimotuzumab with yttrium-90, in order to provide a β- emitting radioimmunoconjugate (90Y-DOTA-nimotuzumab) potentially useful to assess the feasibility of a new radio-guided surgery approach.

Methods: The synthesis of 90Y-DOTA-nimotuzumab was performed in two days. Nimotuzumab was conjugated with a 50-fold excess of DOTA and then labelled with 90Y3+. The 90Y-DOTA-nimotuzumab preparation was optimized considering several parameters such as pH, temperature and reaction volume. Moreover, the 90Y-DOTA-nimotuzumab stability was evaluated in human plasma.

Results: The radioimmunoconjugate 90Y-DOTA-nimotuzumab was obtained with a radiochemical purity greater than 96%, and showed a good stability at 20°C as well as at 37°C in human plasma.

Conclusions: The optimized conditions for a mild and easy preparation of 90Y-DOTA-nimotuzumab joined to a promising stability under physiological conditions suggest to propose this radioimmunoconjugate as a potential diagnostic radiopharmaceutical for β- radio-guided surgery.

Keywords: 90Y-DOTA-nimotuzumab; immunochemotherapy; molecular probe technique; monoclonal antibody; radio-guided surgery; radiopharmaceutical.

MeSH terms

  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Antineoplastic Agents*
  • Heterocyclic Compounds
  • Humans
  • Immunoconjugates* / pharmacology
  • Organometallic Compounds
  • Radiopharmaceuticals / pharmacology
  • Yttrium Radioisotopes / therapeutic use

Substances

  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Antineoplastic Agents
  • Heterocyclic Compounds
  • Immunoconjugates
  • Organometallic Compounds
  • Radiopharmaceuticals
  • Yttrium Radioisotopes
  • yttrium(III)-1,4,7,10-tetraazacyclotetradecane-N,N',N'',N'''-tetraacetic acid
  • Yttrium-90
  • nimotuzumab