This study is for women with endometrial cancer. The purpose is to find out if adding a new immunotherapy drug to the usual combination of chemotherapy drugs can lower the chance of your endometrial cancer growing or spreading.

This study is for adult women who have advanced or recurrent endometrial (uterine) cancer. The purpose is to find out if the drug combination of paclitaxel, carboplatin and metformin works better than paclitaxel and carboplatin alone in treating uterine cancer.