Doctors may be able to identify which HER2-negative breast cancer patients will respond to treatment and which patients should switch to an alternative treatment following a short exposure to a targeted therapy, a study team from Case Western Reserve has reported. Findings from the study are published in International Journal of Cancer.
Bevacizumab (Avastin) was initially approved by the Food and Drug Administration (FDA) in 2008 for use in metastatic HER2-negative cancer, but was later retracted in 2011 after longer-term clinical trials did not show improvements in overall survival compared to other chemotherapy agents.
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Researchers discovered a signature that tells which patients are likely to respond to bevacizumab and chemotherapy within 15 days of the first dose, senior author Lyndsay Harris, MD, professor of medicine at Case Western Reserve, stated. Early results would allow some patients to not experience some of the drug’s severe adverse effects and consider other options.
For the study, a multicenter team assembled to determine if the early success of bevacizumab therapy could be detected or if its significant toxicity would cause more harm than benefit for breast cancer. Tumor tissue from HER2-negative breast cancer patients were analyzed at baseline prior to therapy. Then patients received a single bevacizumab dose and their tissue was examined again 10-14 days later to see what molecular changes occurred. The team found a decrease in TGF-beta signaling activity only in tumors that achieved a complete response. This translates to a >90% cure rate for the patient where tumor cells become more sensitive to treatment likely due to hypoxia.
Study findings may help in identifying biomarkers for bevacizumab in other cancers to determine its efficacy for individual patients with cancer, they concluded.
For more information visit case.edu.