Study of Sacituzumab Govitecan-hziy Versus Treatment of Physician's Choice in Participants With HR+/HER2- Metastatic Breast Cancer

Inclusion Criteria

• Documented evidence of hormone receptor-positive human epidermal growth factor receptor 2 negative (HER2-negative) (hormonal receptor-positive (HR+)/HER2-) metastatic breast cancer (MBC) confirmed.
• Refractory to or relapsed after at least 2, and no more than 4, prior systemic chemotherapy regimens for metastatic disease:
• At least 1 taxane in any setting.
• At least 1 prior anticancer hormonal treatment in any setting.
• At least 1 cyclin-dependent kinase inhibitor 4/6 in any setting.
• Eligible for one of the chemotherapy options listed in the TPC arm.
• Documented disease progression after the most recent therapy.
• Adequate bone marrow function (hemoglobin ≥ 9 g/dL, absolute neutrophil count (ANC) ≥ 1,500 per mm^3, platelets ≥ 100,000 per mm^3).
• Adequate renal function: calculated creatinine clearance ≥ 30 mL/minute according to the Cockcroft and Gault formula .
• Adequate liver function (bilirubin ≤ 1.5 institutional upper limit of normal (IULN), or ≤ 3 IULN for individuals with documented Gilbert's syndrome, aspartate aminotransferase (AST) and Alanine aminotransferase (ALT) ≤ 2.5 x IULN (in the case of liver metastases ≤ 5.0 x IULN)).
• 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.
• History of significant cardiovascular disease or clinically significant electrocardiogram (ECG) abnormality.
• Active serious infection requiring antibiotics.
• Any medical or other condition which, in the opinion of the Investigator, causes the individual to be medically unfit to receive sacituzumab govitecan or unsuitable for any reason.
• Locally advanced MBC (stage IIIc) in individuals who are candidates for curative intent therapy at the time of study enrollment. Note: Other protocol defined Inclusion/Exclusion criteria may apply.