Preparation of 177Lu-Trastuzumab injection for treatment of breast cancer

Abstract The objective of this study was the facile preparation of 177 Lu-CHX-A’’-DTPA-Trastuzumab injection for breast cancer therapy. Trastuzumab conjugated with CHX-A’’-DTPA-NCS was radiolabeled with 177 Lu in >95% radiochemical purity. In vitro studies in SKBR3 and MDA-MB-453 cells confirmed specificity of 177 Lu-CHX-A’’-DTPA-Trastuzumab to HER2 positive cells. The radioimmunoconjugate showed good immunoreactivity, in vitro stability in saline and K d of 1.01 ± 0.13 nM in SKBR3 cells. Clearance of 177 Lu-CHX-A’’-DTPA-Trastuzumab in Swiss mice was predominantly through the hepatobiliary route with minimal bone uptake.