The purpose of this study is to evaluate an experimental drug called sacituzumab govitecan in combination with pembrolizumab, or pembrolizumab with or without capecitabine, in people with high-risk, early triple-negative breast cancer without mutations (changes) in the BRCA1 or BRCA2 gene, who underwent pre-operative chemotherapy and immunotherapy and had residual invasive breast cancer at the time of surgery. Researchers want to determine whether sacituzumab govitecan in combination with pembrolizumab can improve outcomes and delay the return of disease when compared to pembrolizumab alone or pembrolizumab in combination with capecitabine. Sacituzumab govitecan is a type of drug called an antibody-drug conjugate. The antibody attaches to (recognizes) a certain type of protein found on many cancers and is conjugated (attached) to an anti-cancer drug. Pembrolizumab is an antibody and type of immunotherapy that helps the immune system to recognize and fight off cancer cells. Capecitabine is a type of chemotherapy tablet that blocks the ability of cancer cells to make DNA, which stops their ability to grow. Participants will be randomly assigned to receive either the experimental treatment, sacituzumab govitecan in combination with pembrolizumab, or 1 of the following 2 study treatment regimens: pembrolizumab alone or pembrolizumab in combination with capecitabine. The combination of pembrolizumab together with capecitabine is not formally approved by health authorities nor listed in international guidelines. However, it is currently adopted as a primary standard-of-care regimen for patients with triple-negative breast cancer that remains after pre-surgical treatment and surgery. In this study, it is considered standard of care.

• CS Cancer at Beverly Hills : Nikki Kem-Bernard
• CS Cancer at Cedars-Sinai Medical Center : Nikki Kem-Bernard