AGuIX-Bi

AGuIX-Bi is a next-generation theranostic nanoparticle drug designed to enhance the efficacy of radiotherapy in cancer treatment. It is based on the original AGuIX platform, which consists of a polysiloxane matrix with gadolinium chelates. In AGuIX-Bi, approximately 70% of the gadolinium (Gd) atoms are replaced by bismuth (Bi) atoms, resulting in improved radiation dose amplification while maintaining MRI contrast capabilities. The ultrasmall size (~5 nm) allows for selective tumor accumulation after intravenous administration. Mechanistically, the presence of high atomic number elements (Gd and Bi) enhances local radiation-induced DNA damage within tumors (radiosensitization), while Gd provides positive contrast for MRI imaging. Preclinical studies have shown that increasing Bi content leads to greater DNA damage and improved tumor control without observed toxicity[5][6]. The drug is under clinical investigation for multiple solid tumors.