ESR1 and breast cancer: The AMEERA-2 study has demonstrated that amcenestrant has a favorable safety profile in Japanese postmenopausal women with ER + /HER2 − advanced breast cancer, with no grade ≥ 3 TEAEs at a dose of 400 mg QD and a PK profile similar to the one previously observed in a global population of patients (AMEERA-1, Arm 1, Part A).