This study investigates how well the combination of an investigational medication and carboplatin works in treating patients with metastatic triple negative breast cancer. Metastatic means the cancer has spread to other parts of the body. Triple negative breast cancer is a type of breast cancer that does not have any of the three common receptors known to fuel most breast cancer growth. The study compares the effects of using carboplatin alone versus carboplatin with an investigational medication.
Participants will undergo various procedures, including biopsies of metastatic lesions, which are areas where cancer has spread. A biopsy is a medical test where a small sample of tissue is taken for closer examination. The study is randomized, meaning participants are randomly assigned to different study arms, such as receiving carboplatin alone or with the investigational medication.
- Who can participate: Adults with stage IV triple negative breast cancer may participate. Participants must have measurable disease and no more than one prior chemotherapy regimen for metastatic disease. They need to have adequate blood, liver, and kidney function. Participants must also be willing to undergo biopsy of a metastatic lesion.
- Study details: Participants will be randomly assigned to receive either carboplatin alone or in combination with atezolizumab.

