Trastuzumab is a medication primarily used to treat breast cancer that is HER2-positive. As with any medication, there are several synonyms that can be used to describe Trastuzumab. Other names for Trastuzumab include Herceptin, Ogivri, Herzuma, Ontruzant, and Trazimera. These synonyms are used to describe the medication when researching or prescribing it, and they all refer to the same drug. Trastuzumab is a monoclonal antibody that targets the HER2 receptor that is overexpressed in HER2-positive breast cancer cells. This medication has been shown to improve survival rates and quality of life for patients with this type of breast cancer.