The goal of this clinical study is to find out how the study drug, sacituzumab govitecan (SG) works in participants with endometrial cancer who have received prior treatment with platinum-based chemotherapy and immunotherapy, versus the treatment of physician's choice (TPC).

The primary objectives of this study are to evaluate the effect of SG compared to TPC on progression-free survival (PFS) as assessed by blinded independent central review (BICR) and overall survival (OS).

Key Inclusion Criteria:

• Documented evidence of recurrent/persistent endometrial cancer (endometrial carcinoma or carcinosarcoma).
• Up to 3 prior lines of systemic therapy for endometrial cancer, including systemic platinum-based chemotherapy and anti-PD-1/PD-L1 therapy, either in combination or separately.
• Eligible for treatment with either doxorubicin or paclitaxel as determined by the investigator.
• Radiologically evaluable disease (either measurable or nonmeasurable) by computed tomography (CT) or magnetic resonance imaging (MRI) per RECIST v1.1.
• Eastern Cooperative Oncology Group performance status score of 0 or 1.
• Adequate organ function

Key Exclusion Criteria:

• Uterine leiomyosarcoma and endometrial stromal sarcomas are excluded.
• Participants who are candidates for curative-intent therapy at the time of study enrollment.
• Participants eligible for rechallenge with platinum-based chemotherapy as determined by the investigator.
• Received any prior treatment with a Trop-2-directed antibody-drug conjugate (ADC).
• Have an active second malignancy.
• Have an active serious infection requiring systemic antimicrobial therapy.
• Have active chronic inflammatory bowel disease (ulcerative colitis, Crohn's disease) or gastrointestinal perforation within 6 months prior to randomization.
• Have a positive serum pregnancy test or are breastfeeding for participants who are assigned female at birth.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.