Bevacizumab (brand name Avastin)  is an anti-cancer therapy that belongs to a group of drugs called monoclonal antibodies. A monoclonal antibody is a drug created in the laboratory that is designed to target and inhibit certain proteins. These agents are very specific for the molecules that they are created against.

Mechanism of action

Bevacizumab binds to and inhibits the activity of a protein present on the surface of cells called vascular endothelial growth factor (VEGF). This VEGF helps cancer cells to form new blood vessels and by blocking the action of VEGF, bevacizumab stops the cancer from developing its own blood supply

This reduces the tumor’s supply of oxygen and nutrients, causing it to stop growing and shrink. Drugs that interfere with blood vessel growth are called angiogenesis inhibitors or anti-angiogenics.

Clinical uses

The United States Food and Drugs Administration has approved bevacizumab as a first-line treatment for patients with advanced and metastatic (cancer that has spread to vital organs) carcinoma of the colon or rectum.

The therapy can also be used to treat advanced non-small cell lung cancer or advanced cancer of the breast, kidney or bowel. In addition, bevacizumab has been used successfully in the treatment of eye disorders such as age-related macular degenerationand diabetic retinopathy, where abnormal blood vessel growth in the retina causes the vessels to leak fluid, giving rise to retinal damage.

Administration

Bevacizumab may be given in combination with chemotherapy or when used to treat kidney cancer, it may be given alongside interferon. The drug is given as a drip into a vein (infusion) once every two or three weeks. Bevacizumab is usually administered over a period of 90 minutes for the first infusion, 60 minutes for the second infusion, with infusions thereafter lasting for about 30 minutes.