This clinical trial is focused on studying a type of breast cancer known as HER2-positive metastatic breast cancer. This is a form of cancer that has spread beyond the breast and is characterized by an overexpression of the HER2 protein. The study is investigating a treatment called trastuzumab deruxtecan, also known by its code name DS-8201a. This medication is a combination of a HER2-targeted antibody and a topoisomerase I inhibitor, which is designed to target and kill cancer cells more effectively.
The purpose of the study is to evaluate how well trastuzumab deruxtecan works in patients whose cancer has not responded well to previous treatments, specifically those involving trastuzumab, pertuzumab, and taxane. Participants in the study will receive the medication through an intravenous infusion, which means it will be administered directly into a vein. The study will monitor the participants over a period to assess the treatment’s impact on the cancer, including how long it takes for the cancer to progress and the overall survival of the patients.
Throughout the study, researchers will also keep track of any side effects or adverse reactions to the treatment. This will help determine the safety and tolerability of trastuzumab deruxtecan. The study aims to provide valuable information on whether this treatment can be a viable option for patients with HER2-positive metastatic breast cancer who have not had success with other therapies.



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