According to results recently presented at the 2007 annual San Antonio Breast Cancer Symposium, the chemotherapy combination of Ixempra® (ixabepilone) plus Xeloda® (capecitabine) provides anticancer activity among patients with hormone-negative, HER2-negative metastatic breast cancer that has stopped responding to standard therapies including anthracyclines and taxanes.
Metastatic breast cancer refers to breast cancer that has spread from its site of origin to distant sites in the body. The majority of breast cancers are hormone-positive, which means they are stimulated to grow from exposure to the female hormones estrogen and/or progesterone. Breast cancer that is not stimulated to grow from exposure to these hormones is referred to as hormone-negative.
Approximately 25% of breast cancers are human epidermal growth factor receptor 2 (HER2)-positive, meaning that they overexpresses HER2, which is involved in cellular growth and replication. The majority of breast cancers, however, are HER2-negative, meaning that they are not affected by the HER2 pathway. Breast cancers that are not stimulated to grow from exposure to estrogen or progesterone and are HER2-negative are called triple-negative breast cancers. Triple-negative breast cancers tend to be more aggressive than other breast cancers and have fewer options of therapy.
Standard therapy for triple-negative metastatic breast cancers typically includes chemotherapy utilizing agents in the anthracycline and taxane classes. Typically used anthracyclines include Adriamycin® (doxorubicin), Ellence® (epirubicin), and Doxil® (pegylated liposomal doxorubicin), and typically used taxanes include Taxol® (paclitaxel) and Taxotere® (docetaxel). Because patients whose cancer progressed despite treatment with anthracyclines and/or taxanes are left with limited options, researchers continue to evaluate novel therapies to improve their outcomes.
Researchers recently conducted a clinical trial evaluating the newly approved chemotherapy agent Ixempra plus Xeloda for the treatment of triple-negative metastatic breast cancer. This trial included 752 patients whose cancer had progressed despite therapy with anthracyclines and/or taxanes. Patients were treated with either Ixempra plus Xeloda or Xeloda only.
- Anticancer responses were achieved in 27% of patients treated with Ixempra/Xeloda compared with only 9% for those treated with Xeloda only.
- Progression-free survival was doubled among patients treated with Ixempra/Xeloda compared with those treated with Xeloda only.
- The combination of Ixempra and Xeloda was well tolerated.
The researchers concluded that the combination of Ixempra and Xeloda provides improved anticancer response rates and improved progression-free survival compared with Xeloda alone in the treatment of triple-negative metastatic breast cancer that has stopped responding to prior therapy with anthracyclines and/or taxanes.
Patients with triple-negative advanced breast cancer may wish to speak with their physician regarding their individual risks and benefits of all treatment options, including Ixempra.
Reference: Rugo HS, Thomas ES, Lee RK, Fein LE, Peck R, Verrill M. Combination therapy with the novel epothilone B analog, ixabepilone, plus capecitabine has efficacy in ER/PR/HER2-negative breast cancer resistant to anthracyclines and taxanes. Program and abstracts of the 30th Annual San Antonio Breast Cancer Symposium; December 13-16, 2007; San Antonio, Texas. Abstract 6069.