Asian Study of Sacituzumab Govitecan (IMMU-132) in HR+/HER2- Metastatic Breast Cancer (MBC)

Key Inclusion Criteria: * Female or male individuals aged ≥18 years at the time of signing the informed consent form * Documented evidence of hormone receptor-positive HER2-negative (HR+/HER2-) MBC confirmed * Refractory to or relapsed after at least 2, and no more than 4, prior systemic chemotherapy regimens for MBC * Should have been previously treated with at least 1 taxane in any setting, at least 1 prior anticancer hormonal treatment in any setting * Eligible for one of the chemotherapy options listed in the TPC arm * Documented radiographic disease progression after the most recent therapy * Measurable disease by CT or MRI in accordance with RECIST v 1.1, bone-only disease is not measurable and is not permitted. * Adequate bone marrow function, hepatic and renal function * Females must not be lactating or pregnant at Screening or Baseline (as documented by a negative beta human chorionic gonadotropin \[ß-hCG\] Key Exclusion Criteria: * Previous treatment with Topoisomerase 1 Inhibitors as a free form or as other formulations * Individuals who have known brain metastases. * Have an active second malignancy within 3 years prior to providing informed consent * Individuals with active hepatitis B virus (HBV), or hepatitis C virus infection (measurable viral RNA load with polymerase chain reaction). * Active serious infection requiring systemic antibiotic use within 7 days before Cycle1 Day 1. * Other concurrent medical or psychiatric conditions that, in the Investigator's opinion, may be likely to confound study interpretation or prevent completion of study procedures and follow-up examinations. * Known hypersensitivity or intolerance to either of the study treatments or any of the excipients. Note: Other protocol defined Inclusion/Exclusion criteria may apply.