Avastin plus Chemotherapy Improves Survival for Breast Cancer
Preliminary results from a large, randomized clinical trial suggests that a combination of bevacizumab (Avastin) improves progression free survival for patients with metastatic breast cancer (breast cancer that has spread to distant organs) who have received no prior treatments. Those patients who received bevacizumab (Avastin) in combination with standard chemotherapy had a longer time period before their cancer progressed compared to patients who received the same chemotherapy without bevacizumab.
This results comes from a National Cancer Institute (NCI) sponsored clinical trial and conducted by a network of researchers led by the Eastern Cooperative Oncology Group (ECOG). The bevacizumab (Avastin) needed for the trial was provided by Genentech, Inc., South San Francisco, Calif., which manufactures bevacizumab.
The Data Monitoring Committee overseeing the trial recommended that the results of a recent interim analysis be made public because obvious patient management issues since the study had met its primary endpoint of increasing progression-free survival (time prior to progression of breast cancer).
Preliminary data from the trial suggest that patients enrolled in to the study, who received bevacizumab in combination with standard chemotherapy consisting of single-agent paclitaxel (Taxol) had a delay in progression of their cancer by an average of four months, compared to patients treated with paclitaxel (Taxol) chemotherapy alone. This difference in progression free survival is statistically significant.
"This study is the first to find a benefit of anti-angiogenic therapy in patients with breast cancer and represents a major advance in the treatment of patients with metastatic disease," said Study Chair Kathy D. Miller, M.D., of the Indiana University Medical Center in Indianapolis, Ind. Anti-angiogenic drugs, also called angiogenesis inhibitors, are substances that may prevent angiogenesis, or the formation of blood vessels. In anticancer therapy, an angiogenesis inhibitor prevents the growth of blood vessels from surrounding tissue to a solid tumor.
"Recent clinical trials have shown that anti-angiogenic drugs have a favorable impact on colon and lung cancers," said NCI Director Andrew C. von Eschenbach, M.D. "This study demonstrates that when patients with recurrent or metastatic breast cancer received bevacizumab in addition to their chemotherapy, the period of time that they lived with their cancer under control was increased. This is an important step in our journey to ultimately eliminate the suffering and death due to cancer."
The following are the highlights from the study:
- Total number of patients 722
- These patients had recurrent or metastatic breast cancer
- No patient has chemotherapy prior to study
- Patients were randomized to one of the two treatment arms
- One patient group received standard treatment consisting of single-agent paclitaxel
- The second group received the same regimen of paclitaxel plus bevacizumab.
- The following groups of patients were excluded from the study:
- Patients who had overexpressed HER-2 unless they had previously received trastuzumab (Heceptin) or were unable to receive trastuzumab
- Those who have received adjuvant chemotherapy treatment with paclitaxel within the previous 12 months
- Patients with prior history of blood clots or who were on blood thinners
- Serious bleeding and blood clots were rare in this study
- Patients receiving the combination of paclitaxel and bevacizumab had slightly more neuropathy, or problem in peripheral nerve function, abnormally high blood pressure, and protein in the urine, than patients receiving paclitaxel alone
About bevacizumab (Avastin)
Bevacizumab, a humanized monoclonal antibody that already has been approved for metastatic colorectal cancer in combination with chemotherapy
This drug is designed to bind to and inhibit vascular endothelial growth factor (VEGF), which is a protein that plays a critical role in cancer angiogenesis.