Study of Sacituzumab Govitecan in Participants With Metastatic Solid Tumors

Key Inclusion Criteria: * Individuals with the following histologically documented metastatic (M1, Stage IV) or locally advanced solid tumors * NSCLC \[adenocarcinoma or squamous cell carcinoma (SCC)\] that has progressed after prior platinum-based chemotherapy and programmed death-(ligand) 1 (PD-(L)1) directed therapy * HNSCC that has progressed after prior platinum-based chemotherapy and anti-PD-(L)1 directed therapy No more than 3 prior lines of systemic treatment is allowed * Endometrial carcinoma that has progressed after prior platinum-based chemotherapy and anti-PD-(L)1 directed therapy No more than 3 prior lines of systemic treatment is allowed. * Extensive stage SCLC that has progressed after prior platinum-based chemotherapy and PD-(L)1 directed therapy. No more than one prior line of systemic treatment is allowed (re-challenge with the same initial regimen is not allowed) * Eastern Cooperative Oncology Group (ECOG) Performance status score of 0 or 1 * Adequate hematologic counts without transfusional or growth factor support within 2 weeks of study drug initiation * Adequate hepatic and renal function \[Creatinine Clearance (CrCl) ≥30mL/min\] * Individual must have at least a 3-month life expectancy * Have measurable disease by Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) as per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria Key Exclusion Criteria: * Have had a prior anti-cancer biologic agent within 4 weeks prior to study Day 1 or have had prior chemotherapy, targeted small molecule therapy, radiation therapy within 2 weeks prior to Study Day 1 * Have not recovered (i.e., ≤ Grade 1) from adverse events due to a previously administered agent * Have previously received topoisomerase I inhibitors * Have an active second malignancy * Have known active central nervous system (CNS) metastases and/or carcinomatous meningitis. Individuals with previously treated brain metastases may participate provided they have stable CNS disease for at least 4 weeks prior to the first dose of study drug and all neurologic symptoms have returned to baseline, have no evidence of new or enlarging brain metastases and are taking ≤20 mg/day of prednisone or its equivalent. All individuals with carcinomatous meningitis are excluded regardless of clinical stability * Additional cohort specific exclusion criteria Note: Other protocol defined Inclusion/Exclusion criteria may apply.