Bevacizumab (Avastin)

You may have heard about the drug bevacizumab (Avastin), which is used to treat secondary breast cancer (breast cancer that has spread to other sites in the body).

What is bevacizumab?

Bevacizumab, also known as Avastin, is a targeted therapy and is one of a group of cancer drugs known as monoclonal antibodies. It is licensed as a first treatment for secondary breast cancer (also known as metastatic breast cancer).

Clinical trials have explored using bevacizumab in combination with another chemotherapy drug called paclitaxel (Taxol). However, NICE (National Institute for Health and Clinical Excellence) have not recommended this combination.

Other trials are looking at whether bevacizumab is effective in treating breast cancer when used with other chemotherapy drugs and NICE will be deciding whether to approve these combinations.

How does bevacizumab work?

In order for cancers to grow and spread, a constant supply of oxygen and other nutrients are required. Cancers are able to create and maintain this by developing their own blood supply. This process is called angiogenesis.

Bevacizumab is known as an angiogenesis inhibitor. It works by targeting a naturally occurring protein called vascular endothelial growth factor (VEGF), which binds to receptors on blood vessels and stimulates the formation of new blood vessels.

By stopping this process, bevacizumab ‘suffocates’ the blood supply to the cancer, thus shrinking it and stopping it from growing.

How is it given?

Bevacizumab is a colourless fluid given intravenously via a small tube (cannula) inserted into a vein. It is commonly used in combination with paclitaxel.

What are the side-effects of Avastin?

Like any drug, bevacizumab can cause side effects. However, everyone reacts differently to drugs and some people experience more side effects than others. Because it is given with paclitaxel, you may also experience side effects from that drug as well. These side effects may include:

• high blood pressure
• wound healing problems
• lowered resistance to infection
• heart problems
• circulatory problems.