In mouse xenograft studies, PRO1102 demonstrated robust anti-tumor activity across multiple HER2-expressing cell lines that was generally better than ADCs… In addition, PRO1102 retained activity in cancer cells with moderate and low HER2 expression, suggesting the potential to benefit a broader range of patients of HER2-expressing cancers...PRO1102 exhibits the attributes needed for an effective ADC with robust activity in a broad selection of HER2-expressing cancers.