Inclusion Criteria:

          -  Ability to comprehend and willingness to sign a written ICF for the study. Women 18
             years of age or older (or as applicable per local country requirements).

          -  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.

          -  Groups A and B: Have not been previously treated with a PD-(L)1 inhibitor.

          -  Group A only: Tumor tissue tested as MSI-High

          -  Group B only: Tumor tissue tested as deficient MMR or an ultra-mutated POLE tumor.

          -  Group D only: Tumor tissue tested as having an FGFR 1,2,3 mutation or alteration
             characterized as per protocol.

          -  Must have at least 1 measurable tumor lesion per RECIST v1.1.

          -  Willing to provide tumor tissue sample (fresh or archived).

          -  ECOG performance status 0 to 1.

          -  Willingness to avoid pregnancy.

        Exclusion Criteria:

          -  Group A only: Histologically confirmed diagnosis of carcinosarcoma of the uterus.

          -  Histologically confirmed diagnosis of sarcoma of the uterus.

          -  Has disease eligible for potentially curative treatment.

          -  Receipt of anticancer therapy within 28 days of the first administration of study
             treatment, with the exception of localized radiotherapy.

          -  Toxicity of prior therapy that has not recovered to ≤ Grade 1 or baseline unless
             approved by the medical monitor.

          -  Groups C and D (combinations): limiting immune-related toxicity during prior
             checkpoint inhibitor therapy.

          -  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.

          -  Receiving chronic systemic steroids (> 10 mg/day of prednisone or equivalent):

          -  Known active CNS metastases and/or carcinomatous meningitis.

          -  Has known active hepatitis B or C.

          -  Has received a live vaccine within 28 days of the planned start of study treatment.

          -  Evidence of interstitial lung disease or active, noninfectious pneumonitis.

          -  Participants who are known to be HIV-positive with some protocol exceptions.