human absorbed dose estimation of 89zr-anti-her2 complex based on animal data

Introduction: this study aimed to estimate the radiation absorbed dose of human organs after injection of a high-potential pet radioimmunoconjugate of her2+ breast cancers using the medical internal radiation dose (mird) method and the radiation dose assessment resource (radar) formalism.material and methods: 89zr was produced by the nuclear reaction of 89y with protons (p,n), and purified by a column filled with zr resin. the radionuclide, chemical, and radiochemical purities of the 89zr solution were measured using gamma spectrometry, inductively coupled plasma (icp), and radio-thin-layer chromatography (rtlc) methods, respectively. the conjugated anti-her2 with deferoxamine (dfo) was labeled with an in-house produced 89zr at the optimized condition to prepare 89zr-anti-her2, and its radiochemical purity was assessed by the rtlc method. the stability of the radioimmunoconjugate was assessed in phosphate-buffered saline (pbs) buffer and human serum at various intervals. biodistribution of the final complex was studied in tumor-bearing mice at specified intervals. finally, the absorbed dose of human organs was estimated using the mird method and radar formalism based on animal data.results: 89zr radionuclide was produced by the radiochemical and radionuclide purities of >99%, and >99.99%, respectively, while the chemical impurities were < 0.1 ppm. the radiolabeled antibody was prepared with radiochemical purity >98% at optimized conditions. the results showed the liver received the maximum amount of the absorbed dose of 1.49 mgy/mbq, and other organs received < 0.87 mgy/mbq.conclusion: 89zr-anti-her2 complex is a promising agent for pet imaging of patients with her2+ tumors with high safety in the country.