TRAIL-R2 and HER2 Bi-Specific Chimeric Antigen Receptor (CAR) T Cells for the Treatment of Metastatic Breast Cancer

The purpose of this study is to find the biggest dose of HTR2 T cells that is safe, to see how long these cells last in the body, to learn the side effects, and to see if these cells are able to fight and kill HER2 expressing breast cancer. Patients eligible for this study have metastatic breast cancer that has HER2 expression and has progressed on at least one line of therapy. This is a gene transfer research study using special immune cells called T cells. T cells are a type of white blood cell that helps the body recognize and fight cancer cells. The body has different ways of fighting diseases and no single way seems perfect for fighting cancer. This research combines two different ways of fighting cancer: antibodies and T cells. Antibodies are proteins that protect the body from infectious disease and possibly cancer. T cells, or T lymphocytes, are special blood cells that can kill other cells, including tumor cells. Both antibodies and T cells have shown promise treating cancer but have not been strong enough to cure most patients. Previous research has found that investigators can put genes into T cells that helps them recognize cancer cells and kill them. Investigators now want to see if by putting a new gene in those T cells to help recognize breast cancer cells expressing HER2 can kill the cancer cells. In clinical trials for various cancer types that express HER2, our center engineered a CAR that recognizes HER2 and put this CAR into patients own T cells and gave them back. Investigators saw that the cells did grow and patients did tolerate and respond to the treatment. Investigators will add a gene to the HER2 recognizing CAR T cells that will improve the T cells function. Investigators know that some immune cells in the body can lower T cells ability to kill cancer cells. Investigators have identified an antibody that will inactivate those immune suppressive cells thereby allowing T cells to survive better to recognize and kill cancer cells. This antibody targets the Trail-R2 receptor and is referred to as TR2. Also, investigators know that T cells need the support of cytokines to perform their immune functions. There is evidence showing that the addition of interleukin 15 (IL15) enhances CAR T cells ability to kill cancer cells. As a result, investigators also added IL15 to the HER2 and TR2 targeting CAR T cells (HTR2 T cells). The HTR2 T cells are an investigational product not approved by the Food and Drug Administration.