One Dose of Trastuzumab Triggers Immune Response in some Breast Cancers, Study finds
Trastuzumab, an HER2 inhibitor drug, can be effective in treating certain breast cancers, a new study found.
According to the researchers headed by Vinay Varadan, PhD., an assistant professor at Case Western Reserve University School of Medicine, just one dose of the drug triggered an immune response in patients with the HER2-enriched subtype of HER2-positive breast cancer. This subtype of the cancer is estrogen and progesterone receptor negative.
"Our study showed, for the first time, that the immune-cell-activating properties of trastuzumab are likely related to the subtypes of breast cancer," Varadan, who is also a member of the Case Comprehensive Cancer Center, said. "Knowing this can inform future trials studying the usefulness of adding immunotherapy drugs to trastuzumab."
The researchers were able to monitor immune response by measuring the immune activity in tumor tissue via a molecular signature called the Immune Index.
"We found that higher Immune Index evaluated after just one dose of trastuzumab predicted the tumor's response," Varadan said.
Varadan noted that the response appeared to be specific to the drug.
The researchers had examined data gathered from two clinical trials in order to analyze the molecular makeup of the breast cancer in relation to its response to trastuzumab.
They hope that more research into how the tumors respond to trastuzumab can help pave the way for more effective treatment options for patients.
The researchers stated, via Medical Xpress:
"Given that the subtypes of HER2-positive disease and the immune signatures predict response to trastuzumab-based therapy, the next question is whether these signatures can also predict response to dual-HER2 targeted therapy. Additionally, we would like to understand why certain breast cancers have a strong immune response when treated with anti-HER2 therapy while others escape immune surveillance. We are poised to answer these questions using both lab-based research as well as an ongoing preoperative clinical trial-CASE14112-being conducted here at CWRU."
The study was published in the journal, Clinical Cancer Research.