The OlympiA trial (NCT02032823 [68]) will assess the efficacy and safety of up to 12 months of olaparib versus placebo as adjuvant treatment in patients with germline BRCA1/2 mutations and high-risk hormone receptor-negative HER2-negative primary breast cancer who have completed definitive local treatment and neoadjuvant or adjuvant chemotherapy. This evidence concerns the gene ERBB2 and breast cancer.