Bevacizumab for breast cancer hasn't proved to be a particularly effective treatment and might be considered as such only when the drug is combined with paclitaxel. Many health experts believe that the potential side effects of the drug outweigh the possible gains. Other health agencies, however, still believe that a combination treatment with paclitaxel is a suitable treatment. Some patients do show improvement on the drug, but clinical studies have shown that the drug typically has little to no effect.
Tumors, like any other part of the human body, need blood to function. Bevacizumab is a man-made antibody that works by reducing the blood supply to tumors. The tumor then decreases in size or grows much more slowly as a result. It blocks the action of the vascular endothelial growth factor protein, which in turn reduces the blood supply to the tumor. This action has led to bevacizumab being used to treat various cancers, such as kidney, rectal and lung cancers.
Initial studies showed that using bevacizumab in combination with another drug, paclitaxel, could improve survival without progression by about six months. As research continued on the treatment, however, it was found that a more realistic figure would less than one month. This additional research and the generally inconclusive results has curtailed the use of bevacizumab for breast cancer, and in some countries, such as the United States, it is no longer an approved treatment. Other countries still allow this treatment, but only when the drug is combined with paclitaxel.
One reported side effect of the use of bevacizumab is a possibility of tearing in the stomach or intestines, which causes bloody vomit or bleeding in the lungs and can be fatal. Also, side effects such as nausea, loss of appetite and fainting are possible. Despite the risks and various studies that have questioned the effectiveness of bevacizumab for breast cancer, some patients have reported having positive experiences with using the drug.