64Cu-CB-TE2A-G-ZHER2:342

64Cu-CB-TE2A-G-ZHER2:342 is a radiopharmaceutical diagnostic tracer designed for positron emission tomography (PET) imaging of HER2-positive malignancies, such as breast cancer. It consists of the ZHER2:342 Affibody molecule, a small (approx. 6.5 kDa) engineered protein scaffold that binds with high affinity to the extracellular domain of the Human Epidermal Growth Factor Receptor 2 (HER2). The Affibody is conjugated to the cross-bridged chelator CB-TE2A (4,11-bis(carboxymethyl)-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane) via a single glycine (G) spacer and labeled with the positron-emitting radioisotope copper-64 (64Cu). The use of the CB-TE2A chelator is intended to provide high kinetic stability for the radiocopper complex to minimize transchelation in vivo. In preclinical studies, this specific construct demonstrated high tumor uptake but also showed significant hepatic accumulation, leading researchers to conclude that more hydrophilic spacers (such as GEEE) are preferable for optimizing imaging contrast.

Other names

64Cu-labeled Affibody ZHER2:342 with CB-TE2A chelator and glycine spacer