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Trastuzumab works by binding to HER2, a protein involved in cell growth found in large amounts on some cancer cells. This binding blocks the ability of HER2-positive cancer cells to send chemical signals that tell them to grow. It also stimulates the immune system to kill cells that have a lot of HER2. Trastuzumab is a type of targeted therapy drug called a monoclonal antibody.

US Brand Name(s)
FDA Approved

FDA label information for this drug is available at DailyMed.

Use in Cancer

Trastuzumab is approved to be used alone or with other drugs to treat:

Trastuzumab is also available in three different forms, trastuzumab and hyaluronidase-oysk, pertuzumab, trastuzumab, and hyaluronidase-zzxf, and ado-trastuzumab emtansine. For more information, see the Drug Information Summaries for Trastuzumab and Hyaluronidase-oysk, Pertuzumab, Trastuzumab, and Hyaluronidase-zzxf, and Ado-Trastuzumab Emtansine.

Trastuzumab is also being studied in the treatment of other types of cancer.

More About Trastuzumab

Definition from the NCI Drug Dictionary - Detailed scientific definition and other names for this drug.

MedlinePlus Information on Trastuzumab - A lay language summary of important information about this drug that may include the following:

  • warnings about this drug,
  • what this drug is used for and how it is used,
  • what you should tell your doctor before using this drug,
  • what you should know about this drug before using it,
  • other drugs that may interact with this drug, and
  • possible side effects.

Drugs are often studied to find out if they can help treat or prevent conditions other than the ones they are approved for. This patient information sheet applies only to approved uses of the drug. However, much of the information may also apply to unapproved uses that are being studied.

Research Results and Related Resources

Tucatinib and Trastuzumab Combination Approved for Advanced Colorectal Cancer

Targeted Therapy to Treat Cancer

Monoclonal Antibodies

Clinical Trials Accepting Patients

Find Clinical Trials for Trastuzumab - Check for trials from NCI's list of cancer clinical trials now accepting patients.

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