It is also substantially higher than the best tumor-to-liver ratios provided by other HER2-targeting DARPins, such as [111In]In-(HE)3-G3 (12.0 ± 3.6 at 24 h after injection) [8], or [99mTc]Tc(CO)3-(HE)3-G3 (5.9 ± 0.9 at 24 h after injection) [12]. Here, ERBB2 is linked to neoplasm.