Trastuzumab for Injection 440mg is a medication used to treat HER2-positive breast cancer. This works by specifically targeting the HER2 protein, which is abundant in some breast cancer cells. Trastuzumab can slow or stop the growth of cancer cells by binding to HER2. Your doctor will also monitor your reaction to the medication and adjust the dose as needed. Trastuzumab for Injection 440mg should be administered under the supervision of a healthcare professional who can monitor for potential side effects too.