Evaluation of Orally Administered Amcenestrant (SAR439859) in Japanese Postmenopausal Patients With Advanced Breast Cancer (AMEERA-2)

Primary Objective: To assess the incidence rate of dose-limiting toxicity and to confirm the recommended dose as well as the maximum tolerated dose of SAR439859 administered as monotherapy to Japanese postmenopausal women with estrogen receptor positive and human epidermal growth factor receptor 2-negative advanced breast cancer. Secondary Objective: * To characterize the overall safety profile of SAR439859 administered as monotherapy. * To characterize the pharmacokinetic profile of SAR439859 administered as monotherapy. * To evaluate the antitumor activity of SAR439859 administered as monotherapy and the clinical benefit rate (complete response, partial response and stable disease ≥ 24 weeks).