Safety and Efficacy of Retifanlimab (INCMGA00012) Alone or in Combination With Other Therapies in Participants With Advanced or Metastatic Endometrial Cancer Who Have Progressed on or After Platinum-based Chemotherapy.

Inclusion Criteria:

1. Ability to comprehend and willingness to sign a written ICF for the study. Note for Germany: This excludes individuals who are housed in an institution due to official or court order Women 18 years of age or older (or as applicable per local country requirements).
2. Histologically confirmed diagnosis of advanced or metastatic endometrial cancer with disease progression on or after treatment with at least 1 platinum-containing regimen for advanced or metastatic disease.
3. Groups A, B, and E: Have not been previously treated with a PD-(L)1 inhibitor.
4. Group A only: Tumor tissue tested as MSI-High
5. Group B only: Tumor tissue tested as deficient MMR or an ultra-mutated POLE tumor.
6. Group D only: Tumor tissue tested as having an FGFR 1,2,3 mutation or alteration characterized as per protocol.
7. Group E: Tumor tissue tested as MSS and PD-L1 positive.
8. Group F: Radiological evidence of disease progression on or after prior PD (L)1 therapy and Tumor tissue tested as MSI-H
9. Must have at least 1 measurable tumor lesion per RECIST v1.1.
10. Willing to provide tumor tissue sample (fresh or archived).
11. ECOG performance status 0 to 1.
12. Willingness to avoid pregnancy.

Exclusion Criteria:

1. Group A, B and E only: Histologically confirmed diagnosis of carcinosarcoma of the uterus.
2. Histologically confirmed diagnosis of sarcoma of the uterus.
3. Has disease eligible for potentially curative treatment.
4. Receipt of anticancer therapy within 28 days of the first administration of study treatment, with the exception of localized radiotherapy.
5. Toxicity of prior therapy that has not recovered to ≤ Grade 1 or baseline unless approved by the medical monitor.
6. Groups C, D and F (combinations): limiting immune-related toxicity during prior checkpoint inhibitor therapy.
7. Group F only: Previous treatment with LAG-# or TIM-3 therapy or lenvatinib; multiple metastases that achieved mixed tumor response to prior anti-PD-(L)1 therapy
8. Has an active autoimmune disease requiring systemic immunosuppression with corticosteroids (> 10 mg/day of prednisone or equivalent) or immunosuppressive drugs within 14 days before the first dose of study treatment.
9. Receiving chronic systemic steroids (> 10 mg/day of prednisone or equivalent):
10. Known active CNS metastases and/or carcinomatous meningitis.
11. Has known active hepatitis B or C.
12. Has received a live vaccine within 28 days of the planned start of study treatment.
13. Evidence of interstitial lung disease or active, noninfectious pneumonitis.
14. Participants who are known to be HIV-positive with some protocol exceptions.