With these results, a phase 2 clinical trial, ACE-Breast-03, a single-arm study in patients with HER2-positive breast cancer resistant or refractory to T-DM1, T-DXd and prior treatment with tucatinib, was ongoing; however, the pharmaceutical company will no longer directly pursue ARX788 and will pause clinical trials that include ARX788 outside of China and seek a development partner ex-China. This evidence concerns the gene ERBB2 and breast cancer.