A Randomized Phase II Trial of Tamoxifen Versus Z-Endoxifen HCl in Postmenopausal Women with Metastatic, Estrogen Receptor Positive, HER2 Negative Breast Cancer

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Updated on 23 November 2020
breast cancer
estrogen receptor


A Randomized Phase II Trial of Tamoxifen Versus Z-Endoxifen HCl in Postmenopausal Women with Metastatic, Estrogen Receptor Positive, HER2 Negative Breast Cancer


You are being asked to participate in this study because you are a postmenopausal woman with estrogen receptor positive and HER2 negative breast cancer that no longer responds to aromatase inhibitors (anti-estrogen therapy) and has spread in the breast, or to other parts of your body. For patients who receive the usual approach for this cancer, tamoxifen, about 20 out of 100 patients are alive without cancer progression after 1 year of treatment. Estrogen receptor positive means that your cancer is potentially sensitive to anti-estrogen therapy. HER2 negative means that you do not have too many HER2 cells, which can cause breast cancer to grow faster. Postmenopausal women with your type of breast cancer are usually treated with hormonal therapy. The purpose of this study is to compare any good and bad effects of using Z-Endoxifen HCL to using tamoxifen. Z-Endoxifen HCL could shrink your cancer and prevent it from spreading, but it could also cause side effects. This study will allow the researchers to know whether this new approach is better, the same, or worse than the usual approach of using tamoxifen. To be better, the study approach should increase the time to cancer progression by 3 months or more compared to the usual approach. Tamoxifen has been approved by the Food and Drug Administration (FDA) of the United States for the treatment of advanced or metastatic (spread outside of the breast or to other parts of the body) breast cancer. Z-Endoxifen HCl is an investigational or experimental anticancer agent that has not yet been approved by the Food and Drug Administration for breast cancer. Tamoxifen and Z-Endoxifen HCl both work by blocking the effects of estrogen in the breast cancer cells. The study researchers also would like to learn more about fatigue and quality of life. All study participants will be asked to complete a two question questionnaire. It will take less than one minute to complete the questions

Condition Breast Cancer
Clinical Study IdentifierTX143634
Last Modified on23 November 2020


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