ERBB2 and breast cancer: A pivotal trial involving 1836 patients with high‐risk, HER2‐negative early breast cancer and germline BRCA1/2 variants demonstrated that those who received olaparib experienced an improvement in 3‐year disease‐free survival compared to the placebo group (87.5% vs. 80.4%; hazard ratio, 0.57; 99.5% confidence interval, 0.39 to 0.83; p < 0.001).