CHICAGO (Reuters) - People who took Roche’s popular cancer drug Avastin in combination with chemotherapy had a 46 percent higher risk of dying from drug-related side effects than people who got chemotherapy alone, researchers said on Tuesday.
But they said the overall rate of deaths caused by Avastin when used with chemotherapy was still low at 2.5 percent, and that the benefits need to be weighed against the risks.
Roche’s Genentech unit said the analysis, published in the Journal of the American Medical Association, includes data on cancers in which the drug is not approved and should not be used.
Dr. Shenhong Wu of Stony Brook University School of Medicine in New York and colleagues pooled data from 16 previously published trials of patients with different types of cancer and found the rate of deaths was 1.5 times higher among people who took Avastin, or bevacizumab, plus chemotherapy compared with those who got chemotherapy alone.
“We discovered the use of bevacizumab in combination with other chemotherapy or biological therapy increased the risk of treatment-related mortality by 46 percent,” Wu said in a statement.
Avastin, the world’s best-selling cancer medicine with annual sales of $6 billion, has been approved for fighting several different cancers, including certain types of lung cancer, advanced colorectal and kidney cancers.
It had been approved to treat breast cancer, but it failed to help breast cancer patients live longer in four clinical trials, and U.S. regulators in December rescinded its approval in breast cancer.
Avastin blocks vascular endothelial growth factor, or VEGF, which is needed to form blood vessels to feed tumors but also needed for normal blood vessel growth.
Many of the side effects involved bleeding, including hemorrhages, low white blood cell count, holes in the stomach and intestines and blood clots in the lungs.
The team said the overall rate of deaths caused by the drug was 2.5 percent, but the risks varied significantly depending on which chemotherapy drug was used.
Because the absolute risk of treatment-related death appears low, the team said use of Avastin should be considered in the context of its overall survival benefits.
Roche said the data used in the analysis is not new and included data on cancers for which the drug is not approved, including squamous cell, non-small cell lung, prostate and pancreatic cancers.
“Avastin does have serious risks within cancer care which are clearly outlined on its label,” Charlotte Arnold, a spokeswoman for Roche’s Genentech unit, said in a telephone interview.
She said in the indications in which it is approved, the risk-benefit profile is considered favorable.
Dr. Roman Perez-Soler of Montefiore-Einstein Center for Cancer Care in New York who has seen the study but was not involved with the analysis said all cancer drugs have potentially fatal side effects, including chemotherapy.
“We have to put everything in perspective,” Perez-Soler said in a telephone interview.
He said the overall increased risk of taking Avastin should be weighed by the chance that it could extend the lives of gravely ill cancer patients.
“I think we should know that it may happen and be careful in selecting the patients in which we give the drug,” Perez-Solar said. “That is the positive aspect of the article.”
Editing by Maggie Fox and Jackie Frank