Ramping Up the Immune System to Fight Breast Cancer
When it comes to immunotherapy, a tumor’s classification as hot or cold is important. Hot refers to tumors showing signs of inflammation, meaning the immune cells have recognized and responded to the malignant cells. These types of tumors respond well to immunotherapy because the immune system is already activated. Cold tumors, on the other hand, contain immune suppressive cells and are more difficult to treat. Breast cancer was once regarded as a cold tumor disease and therefore difficult to treat with immunotherapy, but that is changing thanks to research happening at Moffitt Cancer Center.
A new clinical trial led by Dr. Heather Han is evaluating a combination therapy utilizing two immunotherapies (dendritic cell vaccine and pepinemab), along with trastuzumab followed by adoptive T cell therapy, for patients with metastatic HER2 positive breast cancer. Information about this trial is being presented at the American Society of Clinical Oncology Annual Meeting trial in progress session.
“The goal of this therapy is to activate the immune system and create a hot tumor environment so we can collect those immune cells to create a specific cellular immunotherapy to better target their cancer,” said Han, clinical research director in the Department of Breast Oncology at Moffitt.
The phase 1 trial is recruiting 28 patients. Each patient will receive six weekly injections of a dendritic cell vaccine, in combination with trastuzumab and pepinemab infusions. The dendritic cell vaccine will stimulate the immune system to fight the cancer, and pepinemab will change the tumor microenvironment by increasing infiltration of immune cells and decreasing immunosuppressive cells.
“We hypothesize these therapies together can elicit CD4+, HER2-specific T-cell responses, allowing for adoptive T-cell therapy,” Han said. “For that therapy, we collect blood following the initial immunotherapy and send it to the Moffitt cell therapy lab where they can grow and multiply by the thousands.”
The expanded cells are then infused back into the patient. Trastuzumab and pepinemab will be given as maintenance for three weeks, in addition to booster dendritic cell vaccines.
The clinical trial is ongoing. Han says this combination therapy could provide a new option for HER2 positive breast cancer patients with metastatic disease.
