Better known by its trade name of Herceptin, Trastuzumab is a synthetic monoclonal antibody that was introduced in 1998 and targets breast cancer cells that are HER2 (human epidermal growth factor receptor 2/neu) positive. Herceptin attaches itself to the HER2 protein receptors on the surface of cancer cells and slows the growth and spread of the tumour and its secondaries.
It is given intravenously (injected into a vein) but does not require hospitalisation but is only appropriate in those women whose cancer is HER2 positive. HER2 positive breast cancer is a more aggressive disease with a greater likelihood of recurrence and a decreased chance of survival compared with HER2 negative breast cancer.
It may be given in combination with other medications such as paclitaxel.
The side effects may include congestive heart failure, low blood pressure, shortness of breath, lung damage and severe allergy reactions.
Herceptin increases patient survival time and significantly reduces the number of deaths from breast cancer.