Clinical Trials; Breast Cancer
July 27, 2020
When treating a patient with breast cancer, how do we maximally stimulate immune cells to recognize and kill tumor cells?
The Breast Cancer group at UT Southwestern is steadily growing the number of immunotherapy-focused clinical trials for patients with breast cancer. Our investigator-initiated clinical trials constitute a program that not only investigates how therapies might improve patient outcomes but also uses patient tissues and laboratory science to understand the interactions between tumor cells and the patient’s immune response to improve on treatment options. By conducting and linking science to the clinical trials, we can guide our next steps and improve patient survival rates.
Currently, we are initiating immunotherapy clinical trials for all three subtypes of breast cancer: triple-negative breast cancer, hormone receptor (HR)-positive breast cancer, and human epidermal growth factor receptor 2 (HER2)-negative breast cancer. Although most of the trials are in the metastatic setting, we are also initiating immunotherapy-focused clinical trials for localized breast cancer.
“ From patients and their tumors, we are learning how to personalize breast cancer treatment, both for the current patients and for the benefit of future generations. To do this, we are conducting single-cell sequencing and multiplex immunohistochemistry experiments to understand what is happening in individual immune and tumor cells in the patient.”
One unique clinical trial that my group is participating in is the NIMBUS (Nivolumab Plus Ipilimumab in Metastatic Hypermutated HER2-Negative Breast Cancer) trial. We are one of only three sites in the country with this trial open. For this study, we are recruiting patients who have tumors with a high total mutational burden (more than 10 mutations per megabase of DNA), which account for approximately only 5% to 8% of breast cancers. However, we believe these breast cancers will be the most likely to respond to immunotherapies: The mutational burden indicates that the cancer cells have more abnormalities, increasing the likelihood that the patient’s immune system will recognize these cells as foreign entities and attack. Administering immunotherapy to the patient would enhance that response. We will also assess certain biomarkers in the blood or tumor tissue for prognostic value.
From patients and their tumors, we are learning how to personalize breast cancer treatment, both for the current patients and for the benefit of future generations. To do this, we are conducting single-cell sequencing and multiplex immunohistochemistry experiments to understand what is happening in individual immune and tumor cells in the patient. These studies can show us how cells differ in the cancer environment, where they are, and how they are interacting with each other. In doing so, we are attempting to systemically and rationally identify the best ways to treat breast cancer patients by developing clinical trials unique to their cancer type. In the context of the trial, we allocate time and resources to study patients’ tissues with specific scans and assays to confirm that their tumors are responding as expected, and if they are not responding, learn why and what resistance mechanisms might have developed in the tumor.
UT Southwestern has a strong track record of scientific achievements, particularly in the field of immunology. We have a multidisciplinary team that works together to ensure the best possible care for our patients. Our experts, including breast cancer specialists, medical oncologists, surgical oncologists, radiation oncologists, and radiologists, come together regularly to develop the treatment for each patient. Our team also includes a social worker, a dietitian, and midlevel providers, allowing us to provide comprehensive care. Additionally, our clinical trial team is well integrated with the rest of team, so we can seamlessly incorporate new best practices and decisions based on clinical trials that might become a standard of care option.
Lastly, none of these clinical advances would be possible without the patients and their willingness to participate in our studies. They truly make this a team science effort.
About the Author
Sangeetha Reddy, M.D., M.S.C.I., is a faculty member in the Department of Internal Medicine at UT Southwestern Medical Center, as a breast medical oncologist. Dr. Reddy is a clinical trialist and translational investigator with a research interest in improving outcomes of breast cancer patients through immunotherapy.