This clinical trial is focused on studying treatments for advanced breast cancer in postmenopausal women. The study involves a medication called amcenestrant (also known by its code name SAR439859), which is being tested both on its own and in combination with other cancer treatments. These additional treatments include palbociclib (marketed as IBRANCE), abemaciclib (marketed as Verzenios), everolimus, and alpelisib. The purpose of the study is to evaluate the safety and effectiveness of these treatments in women whose cancer is positive for estrogen receptors (ER-positive) and negative for HER2 receptors.
The study will begin with a phase where the safety of different doses of amcenestrant is assessed, both alone and in combination with the other medications. This phase will help determine the most suitable dose for further testing. Following this, the study will expand to evaluate how well the treatment works in reducing cancer size or slowing its growth. Participants will take the medications orally, and the study will monitor their response to the treatment over time.
Throughout the study, researchers will keep track of any side effects experienced by participants and measure how the cancer responds to the treatment. The study aims to find the best dose of amcenestrant and its combinations that can be safely used to treat advanced breast cancer. The trial is expected to continue until the end of 2027, providing valuable information on the potential benefits and risks of these treatments for women with this type of cancer.



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