Study Comparing Dostarlimab with Chemotherapy to Placebo with Chemotherapy in Advanced Endometrial Cancer

Inclusion Criteria

• Women aged 18 or older.
• Diagnosed with advanced or returning endometrial cancer.
• Cancer is at Stage III or IV, or has returned after initial treatment, and cannot be cured with surgery or radiation alone.
• Must meet specific criteria based on cancer stage and type.
• Must not have had more than one recurrence of cancer.
• Must be in good overall health with an ECOG performance status of 0 or 1.
• Must have normal organ function.

Part 2 only:

• Must have normal or well-controlled blood pressure.
• Must be able to take oral medication.

Exclusion Criteria

• Have had more than one recurrence of endometrial cancer.
• Have received certain cancer therapies recently or have not recovered from previous treatments.
• Have another active cancer or have had one in the last three years, except for certain skin cancers.
• Have uncontrolled cancer spread to the brain or spinal cord.
• Have not recovered from major surgery complications.
• Are currently in another clinical trial or have been recently.
• Have serious uncontrolled medical conditions or infections.
• Have received a live vaccine recently.

Part 2 only:

• Have received a PARP inhibitor before.
• Have significant heart disease.
• Have a history of certain blood disorders.
• Are at risk of bleeding due to other conditions.
• Have participated in Part 1 of this study.