This study is looking at HER2-positive breast cancer, which is a type of breast cancer where cancer cells have high levels of a protein called HER2. The study will test a medication called zanidatamab, also known as JZP598, given before surgery along with different chemotherapy medicines. The chemotherapy medicines that may be used include paclitaxel, docetaxel, and carboplatin. Some participants will receive zanidatamab with paclitaxel, others will receive zanidatamab with docetaxel and carboplatin, and another group will receive trastuzumab with pertuzumab along with docetaxel and carboplatin. After completing the treatment period, participants may also receive trastuzumab emtansine or paclitaxel albumin-bound. All study medicines are given through a vein as an infusion.
The purpose of this study is to find out how many people in each treatment group have no remaining cancer or only a small amount in the breast and nearby lymph nodes after receiving the study treatment and before having surgery. The study will also look at how safe these treatments are, what side effects they may cause, and how they affect the body. Additionally, the study will examine whether participants are able to have surgery as planned and will follow participants over time to check if the cancer comes back and how long they survive.
Participants in this study will be randomly assigned to one of the treatment groups and will receive the study medicines for several months before having surgery to remove the cancer. During the study, participants will have regular visits where doctors will perform examinations, take blood samples, and do heart tests to check how the treatment is working and monitor for any side effects. Participants will also be asked to complete questionnaires about how they are feeling and any symptoms they may be experiencing. After surgery, participants will continue to be followed to see how well the treatment worked and to monitor their overall health.



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