Previously reported findings from the Phase III OlympiAD trial demonstrated a significant improvement in progression-free survival (PFS) with olaparib tablet monotherapy versus chemotherapy treatment of physician’s choice (TPC) in patients with a germline BRCA1/2 mutation (gBRCAm) and human epidermal growth factor receptor 2 (HER2)-negative metastatic BC (mBC)9. This evidence concerns the gene ERBB2 and breast cancer.