Trastuzumab is used to treat some types of breast cancer, and cancers of the stomach and oesophagus (food pipe). It may be used alone or together with other chemotherapy medicines to destroy cancer cells or slow down their growth.
- Trastuzumab belongs to a group of targeted therapies called monoclonal antibodies.
- It is called targeted therapy because it specifically controls cancer cells that have high levels of human epidermal growth factor receptor 2 (HER2). HER2 is found in all human cells.
- High levels of HER2 are found in some types of breast, oesophageal and stomach cancer, and that helps the cancer cells grow and survive. These are known as HER2 positive cancers. About 1 in 5 breast and stomach cancers are HER2 positive.
- Trastuzumab works by attaching to HER2 on the surface of the cancer cells and this stops the cancer cells from growing or multiplying. Trastuzumab also tells your immune system to destroy the cancer cells it's attached to.
Trastuzumab is a biological medicine
Unlike most other medicines that are made from synthetic or man-made chemicals, trastuzumab is made from living sources like bacteria, yeast, or cells from animals and plants.
There are 2 brands of trastuzumab available in Aotearoa New Zealand
- The original brand of trastuzumab is called Herceptin.
- Herzuma is a very close, but not identical, copy of Herceptin. It's called a biosimilar medicine. Read more about biosimilar medicines.
December 2023: The funded brand of trastuzumab is changing
From December 2023, a new brand of trastuzumab, Herzuma will be funded. Herzuma is a biosimilar to the original brand of trastuzumab called Herceptin. This means it’s a very close, but not identical copy of Herceptin. Find out more about Herzuma(external link).