In a combined analysis of two phase I studies in HER2-positive solid tumors in the U.S. and Australia (ACE-Pan tumor-01) and in HER2-positive breast cancers in China (ACE-Breast-01), ARX-788 was well tolerated, with most adverse events (AEs) being grade 1 or 2 [22]. This evidence concerns the gene ERBB2 and breast carcinoma.