Clinical Trials Search at Vanderbilt-Ingram Cancer Center

This phase II trial investigates the effect of avelumab or hydroxychloroquine sulfate with or without palbociclib in treating patients with stage II-III breast cancer that is positive for disseminated tumor cells (DTCs) after curative therapy. DTCs are breast cancer cells that are asleep (dormant) in the bone marrow. There are multiple ways in which these cells stay alive, and three of these mechanisms are inhibited by the drugs in this trial. First, dormant cancer cells need a protein signal pathway involving CDK 4/6 to start dividing once they wake up in order to survive as an active cancer cell. Palbociclib works by blocking the CDK 4/6 protein and by doing so may limit the dormant cancer cell from being able to survive. In addition, palbociclib may also help both of the other drugs in the trial to work better. Second, dormant cancer cells also use a process called autophagy to generate their own nutrition, which can allow them to stay asleep. Hydroxychloroquine has been shown to block autophagy, which leads to starvation of the cells. Third, dormant cancer cells are able to hide from the bodys immune system. The immune system sends a type of cell called T cells throughout the body to detect and fight infections and diseasesincluding cancers. One way the immune system controls the activity of T cells is through the PD-1/PD-L1 (programmed cell death protein-1) pathway. However, some cancer cells hide from T-cell attack by taking control of the PD-1/PD-L1 interaction and this stops T cells from attacking cancer cells. Avelumab is an antibody designed to block the PD-1/PD-L1 pathway and helps the immune system in detecting and fighting dormant cancer cells. Because palbociclib, hydroxychloroquine, and avelumab work on the mechanisms that keep the dormant cells alive, taking one or a combination of these drugs may be able to eliminate DTCs.