Zometa Enhances Chemotherapy Impact On Reducing Breast Tumor Size
New data released today demonstrate that the addition of Zometa (zoledronic acid) injection to standard chemotherapy before breast cancer surgery reduces the size of breast tumors more effectively than chemotherapy alone in women with early-stage disease.
These neo-adjuvant subset results from the retrospective exploratory analysis of the international AZURE (Adjuvant Zoledronic acid to redUce REcurrence) trial are the first to show the direct effect of Zometa in combination with chemotherapy to help shrink cancerous breast tumors, potentially resulting in less radical surgery for some women. The data were presented at the 31st Annual CTRC-AACR San Antonio Breast Cancer Symposium.
"These results support a potential anti-tumor benefit of combining Zometa with chemotherapy in the neoadjuvant treatment of breast cancer," said Matthew Winter, MBChB MSc, Clinical Research Fellow, University of Sheffield, UK, a lead investigator of this subset analysis. "Adding Zometa to chemotherapy prior to surgery increased tumor shrinkage in this analysis. When breast cancer treatment is given prior to surgery, the goal is to reduce the size of the tumor and in doing so potentially improve breast conservation rates and longer-term outcomes."
In the analysis, pre- and postmenopausal women who received Zometa in addition to chemotherapy before surgery (neo-adjuvant use) experienced a significant 33% reduction in the size of their primary tumor (14.1 mm reduction in tumor size) compared with patients who received chemotherapy alone (P=0.002)(1). The proportion of patients requiring mastectomy was higher (77.9%) in the chemotherapy-alone group than in the Zometa group (65.3%).
"Clinical evidence continues to demonstrate that Zometa may play a role in protecting patients from the return and spread of early-stage breast cancer," said David Epstein, President and CEO, Novartis Oncology. "We are encouraged by these latest results, which show Zometa may help some women avoid mastectomies, and we remain committed to further exploring the benefit of Zometa as an anticancer treatment."
Zometa is the world's leading treatment to reduce or delay bone complications in patients with advanced cancer that has spread to the bones across a broad range of solid tumors, including breast cancer.
The potential anticancer properties of Zometa were previously observed in premenopausal women with early-stage breast cancer from the Austrian Breast & Colorectal Cancer Study Group-12 (ABCSG-12) study, which was presented at the American Society of Clinical Oncology annual meeting (ASCO) earlier this year. Final results from the AZURE trial are expected in the next two to three years.
Novartis is further exploring the anticancer effect of Zometa in a broad clinical program in breast, lung and prostate cancers with the results expected over the next two to three years. Laboratory research has suggested that Zometa may help protect patients with early-stage breast cancer from the return or spread of the cancer to other parts of the body (distant metastatic sites) through several different pathways, including inhibiting angiogenesis (formation of blood vessels that grow and feed cancer cells), stimulating cancer-fighting T-cells, inducing tumor cell apoptosis (programmed cell death) and increasing the activity of anticancer agents that target tumor cell metastases(2).
AZURE is a randomized, open-label, multicenter, parallel group trial with a five-year treatment phase and a subsequent five-year follow-up phase designed to determine whether Zometa, added to standard therapy (chemotherapy and/or hormonal therapy) before (neo-adjuvant) or after (adjuvant) surgery, is superior to each therapy alone in improving disease-free survival in pre- and post-menopausal women with early-stage breast cancer. The trial includes 3,360 patients from 174 centers in seven countries and is coordinated by the Cancer Research Centre, Weston Park Hospital, Sheffield, England with support from Novartis(1).
The neo-adjuvant subset in the current analysis included 205 participants who received either chemotherapy alone or in combination with Zometa once every three to four weeks for six months prior to breast cancer surgery. Following adjustment for other prognostic factors, the adjusted mean tumor size after treatment was 28.2 millimeters in the Zometa group and 42.4 millimeters in the chemotherapy group, a significant reduction of 33%(1). The pathologic complete response rate (no evidence of residual cancer in the breast or lymph nodes) increased to 10.9% in the Zometa group from 5.8% in the chemotherapy group (P=0.033). The proportion of women needing a mastectomy was reduced by 16% in patients taking Zometa (65.3% in the Zometa group versus 77.9% in the chemotherapy-alone group)(1).