Using sacituzumab govitecan for treating relapsed ovarian, endometrial, and cervical cancers

* INCLUSION CRITERIA:

Cohort 1 (Ovarian Cancer)

* Participants must have histologically or cytologically confirmed recurrent platinum-resistant (defined as less than six months of platinum-free interval) epithelial (i.e., high grade serous, endometrioid, low grade serous, or clear cell) ovarian carcinoma that is refractory to standard treatment.
* Participants with known BRCA mutated tumors should have received a PARP inhibitor maintenance or treatment.
* Participants without known BRCA mutation and platinum-resistant tumors must have had prior bevacizumab or not eligible for bevacizumab-based therapy (i.e., history of proteinuria).

Cohort 2 (Endometrial Cancer)

* Participants must have histologically or cytologically confirmed recurrent epithelial (i.e., endometrioid or serous) endometrial carcinoma that is refractory to standard treatment.
* Participants must have received prior anti-PD-1/PD-L1-based therapy or not eligible for anti-PD-1/PD-L1-based therapy.

Cohort 3 (Cervical Cancer)

-Participants must have histologically or cytologically confirmed recurrent epithelial cervical (i.e. squamous or adeno) carcinoma that is refractory to standard treatment.

Note: Participants with a history of human papilloma virus infection (i.e., positive HPV DNA testing) are eligible.

-Participants must have received prior bevacizumab-based therapy or not eligible for bevacizumab-based therapy (i.e., history of proteinuria).

Note: Platinum chemotherapy administered concurrent with primary radiation (i.e., weekly cisplatin) is not counted as a systemic chemotherapeutic regimen for management of persistent or recurrent carcinoma of the cervix.

All Cohorts

* Participants must have received at least two systemic therapies including at least one platinum-based therapy regimen.
* Participants must have radiographically measurable disease, per RECIST 1.1, and safely biopsiable lesion.
* Age \>= 18 years
* ECOG performance status \<= 1
* Adequate organ and marrow function as defined below:

  * Hemoglobin (Hgb) \>= 9.0 g/dL
  * Absolute neutrophil count (ANC) \>= 1,500/mcL
  * Platelets \>= 100,000/mcL
  * White Blood Cell count (WBC) \>= 3,000/mcL
  * Total bilirubin \<= 1.5 x upper limit of normal (ULN) (\<= 3 x ULN in participants with known/suspected Gilbert s disease)
  * Aspartate aminotransferase (AST) / Alanine aminotransferase (ALT) \<= 2.5 x ULN
  * Serum creatinine \<= 1.5 x ULN or estimated GFR \>= 30 ml/min/1.73 m\^2
* Participants with suspicion or prior history of treated central nervous system (CNS) metastases with no evidence of active disease (assessed by MRI or contrast CT scan of the brain and spinal column) are eligible if pretreatment brain MRI demonstrate no evidence of disease in the past 4 weeks prior to entry.
* Major surgical procedure, other than for diagnosis, must not occur within 4 weeks prior to the first dose of study treatment. Participants must have recovered adequately from the toxicity and/or complications from the intervention prior to starting the study drug.
* Participants with prior cancer-directed therapy must have a washout period of 3 weeks prior to the first dose of study treatment.
* Participants with prior cancer-directed immunotherapy-based therapy must have a washout period of 4 weeks prior to the first dose of study treatment.
* Human immunodeficiency virus (HIV)-infected participants are eligible if on stable dose of highly active antiretroviral therapy (HAART), a CD4 count \>= 200 cells/mcL, and an undetectable viral load (VL).
* Hepatitis B virus (HBV) positive participants are eligible if they have been treated or are on an appropriate course of antivirals at study entry.
* Participants with a history of hepatitis C virus (HCV) infection (i.e., positive HCV antibody test) must have been treated and cured (undetectable HCV VL at screening). Participants with HCV infection who are currently on treatment are eligible if they have an undetectable HCV VL.
* Individuals of child-bearing potential (IOCBP) must agree to use an effective method of contraception (barrier, surgical sterilization, abstinence) prior to study entry, for the duration of study participation, and for at least 6 months after the last dose of study drug.
* IOCBP must undergo pregnancy testing at screening and must not be pregnant in order to take part. Note: In these cases, a negative Beta-human chorionic gonadotropin (Beta-hCG) (urine or blood) is required.
* Nursing participants must discontinue nursing and/or not begin nursing until 1 month after the last dose of study drug.
* Ability of participants to understand and the willingness to sign a written informed consent document.

EXCLUSION CRITERIA:

* Participants who are receiving any other investigational agents
* Primary platinum-refractory ovarian cancer (defined as progression while on the upfront platinum-based therapy)
* Participants with any other concomitant invasive malignancies
* History of severe hypersensitivity or allergic reactions attributed to compounds of similar chemical or biologic composition to SG, SN-38, or irinotecan.
* Prior treatment with TROP2-targeting ADC. Participants with prior use of other ADCs are eligible.
* Prior treatment with topoisomerase 1 inhibitors i.e., topotecan
* Symptomatic or untreated brain/CNS metastases
* Participants who require treatment with UGT1A1 inhibitors.
* Participants with known homozygous UGT1A1\*28 allele if tested during the previous treatment.
* Participants with active infection requiring antibiotics.
* Participants who have not recovered from toxicities or AEs related to prior therapy to Grade \<= 1 with the following exceptions.

  * Participants with platinum related hypomagnesemia (on replacement) are eligible.
  * Participants with auto-immune thyroid dysfunction on stable replacement therapy are eligible.
  * Participants with any grade alopecia or grade 1 or 2 neuropathy are eligible.
* Participants with a history of gastrointestinal (GI) perforation or hemorrhage (\> 30mL bleeding/episode) fistula or hemoptysis within 3 months prior to initiation of study therapy, intra-abdominal abscess in the 6 months prior to entry, history of ascites or pleural effusion requiring paracentesis or thoracentesis in the 4 weeks prior to initiation of study therapy or history of bowel obstruction within 3 months prior to initiation of study therapy.
* Treatment with a live, attenuated vaccine within 4 weeks prior to initiation of study treatment, or anticipation of need for such a vaccine during SG treatment or within 5 months after the final dose of SG. Note: Seasonal flu vaccines that do not contain a live virus and locally authorized/approved COVID-19 vaccines are permitted
* Participants with severe uncontrolled intercurrent illness that would limit compliance with study requirements, evaluated by history, physical exam, and chemistry panel.