Actually, two PI3K/AKT/mTOR pathway inhibitors are approved for the treatment of metastatic (M) BC: Everolimus, in combination with Exemestane, in HR+/HER2− endocrine resistant MBC and Alpelisib, in combination with Fulvestrant in the case of PI3K-mutated tumors. The gene discussed is ERBB2; the disease is breast cancer.