Avastin can increase fatal side effects in cancer sufferers

A leading cancer drug may increase the risk of death from treatment side effects in some patients, research has shown. This is one of the most economically successful cancer medicines in the world but seems to cause more fatal side effects than previously realized, says a new study.

Avastin, one of a new generation of antibody drugs, was found to increase the likelihood of patients dying when combined with certain chemotherapeutic agents, a blockbuster drug with more than $ 5.5 billion in global revenue, increases the rate of fatal side effects with almost 50% when added to traditional chemotherapy, compared with chemotherapy alone.

However, the overall incidence of fatal side effects (FAEs) associated with the drug low of 2.5%. About 2.5% of cancer patients, combining Avastin and chemotherapy died of treatment - instead of the disease, according to an analysis of 10 217 patients in the current Journal of the American Medical Association. In comparison, 1.7% died of cancer patients who received only conventional chemotherapy as a result of therapy.

Experts say patients who received Avastin - also known by its scientific name bevacizumab - should be monitored closely and a decision on whether the benefits outweighed risks. Researchers analyzed data from 16 studies with a total of 10 217 patients with a variety of advanced solid tumors.

The most common causes of death were bleeding, loss of infection-fighting white blood cells, and perforations in the stomach or intestine, says Shenhong Wu of Stony Brook University School of Medicine, co-author of the analysis of 10 217 patients.

Avastin works by blocking the growth of blood vessels that feed cancer, and oftentimes used in conjunction with standard forms of chemotherapy. The central dilemma of whether Avastin, however, is that doctors today have no way of knowing which patients will benefit, says Daniel Hayes of the University of Michigan Comprehensive Cancer Center, who wrote an accompanying editorial.

The study found that compared with chemotherapy alone, the addition of Avastin is associated with a 1.46 times increase in the risk of an FAE. Doctors tend to give it to all eligible patients, hoping for the best, but to know that Avastin can sometimes hasten a patient's death, says Hayes.

A more than three-fold increase in risk was seen in patients who received taxanes or platinum agents. Internal bleeding in the gut and the lungs were responsible for most deaths.

Patients' willingness to try the drug has benefited Avastin, the total costs of the drug can exceed $ 100,000 a year - it has become the best-selling cancer treatment in the United States, according to IMS Health. Genentech scientists are actively looking for tests to help predict how patients will respond to Avastin, said company spokeswoman Charlotte Arnold.

Researchers led by Dr Vishal Ranpura, from Stony Brook University Medical Center in New York, reported the findings in the Journal of the American Medical Association.

Posted on Wednesday, February 02, 2011. Filed under cancer , general health , headlines . You can follow any responses to this entry through the RSS 2.0