Trastuzumab is a biological medicine. It's used to treat some types of cancer including breast cancer in women, breast cancer in men, oesophageal cancer and stomach cancer.
Trastuzumab is known as a targeted therapy. Targeted therapies are medicines that change the way cells work and help to stop cancer from growing and spreading. Trastuzumab helps to control cancer cells that contain high amounts of HER2 (human epidermal growth factor receptor 2).
HER2 is found in all human cells. It controls cell growth and repair. High levels of HER2 are found in some types of breast, oesophageal and stomach cancer, which helps the cancer cells grow and survive. These are known as HER2 positive cancers. Around 1 in 5 breast and stomach cancers are HER2 positive.
Trastuzumab is available on prescription. It's given in a hospital or clinic as a drip (infusion) or an injection into your thigh (subcutaneous).
Herceptin is the brand name of the original trastuzumab medicine.
There are now other versions of trastuzumab, known by the brand names Herzuma, Kanjinti, Ontruzant, Trazimera and Zercepac. These are biosimilars which are like the original biological medicine. These versions all contain trastuzumab on its own. You'll be prescribed trastuzumab using one of these brand names.
Key facts
- Trastuzumab works by blocking the effects of HER2 and encouraging the immune system (your body's natural defences) to attack and kill the cancer cells.
- The most common side effects of trastuzumab include feeling tired or dizzy, problems sleeping and diarrhoea.
- Your doctor will monitor your heart while you're on treatment and for some time after you stop.
- Trastuzumab may work more quickly for some people than others. You'll have regular check-ups while you're having treatment to make sure it's working well for you.
- It may take over 6 months for trastuzumab to leave your body. Tell your doctor, pharmacist or nurse if you start any new medicine or need to have any vaccines. If your immune system is weak you need to avoid live vaccines.