Preclinical Comparison of [¹¹¹In]In- and [²²⁵Ac]Ac-DOTA-Trastuzumab IgG, F(ab')₂ and Fab for Theranostic SPECT/CT Imaging and α-Particle Radioimmunotherapy of HER2-Positive Human Breast Cancer.

ABSTRACT: Radioimmunotherapy (RIT) with α-particle-emitting, ²²⁵Ac complexed to trastuzumab may offer an alternative treatment for patients who progress on HER2-targeted therapies. Moreover, RIT with [²²⁵Ac]Ac-DOTA-trastuzumab could be combined with SPECT/CT imaging with [¹¹¹In]In-DOTA-trastuzumab in a theranostic approach. In this study, we compared DOTA-conjugated trastuzumab IgG, F(ab')₂ or Fab complexed to ¹¹¹In or ²²⁵Ac for SPECT/CT imaging and α-particle RIT of subcutaneous (s.c.) HER2-positive 164/8-1B/H2N.luc⁺ human BC tumors in NRG mice. SPECT/CT imaging and tumor and normal tissue uptake were compared in NRG or NOD-SCID mice coinjected i.v. with [¹¹¹In]In-DOTA-trastuzumab IgG, F(ab')₂ or Fab

SUBMITTER: Kondo M 

PROVIDER: S-EPMC11708818 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature