Lower tumor uptake of [64Cu]Cu-NOTA-EGF compared to other agents may be due to its more rapid elimination from the blood, since blood activity at 48 h p.i. (0.4 ± 0.1% ID/g; p < 0.05) was significantly lower than [64Cu]Cu-NOTA-trastuzumab Fab-PEG24-EGF bsRICs (1.3 ± 0.2% ID/g) or [64Cu]Cu-NOTA-trastuzumab Fab (1.2 ± 0.2% ID/g), whereas there were no significant differences in blood activity between [64Cu]Cu-NOTA-trastuzumab Fab-PEG24-EGF and [64Cu]Cu-NOTA-trastuzumab Fab. Here, EGF is linked to neoplasm.