FDA withdraws backing for Avastin to treat breast cancer

In an unusual move, the United States Food and Drug Administration has begun the process of withdrawing its approval to use bevacizumab (Avastin) to treat metastatic breast cancer. The drug was approved for breast cancer in 2008 under the FDA’s accelerated approval program.

The FDA based its decision on evidence from 4 independent studies indicating that the benefits of bevacizumab don’t outweigh the risks, which include massive bleeding, severe hypertension, arterial and venous thrombosis, heart attack, stroke, and kidney damage.

“None of the studies demonstrated that patients receiving Avastin lived longer, and patients receiving Avastin experienced a significant increase in serious side effects,” explained Janet Woodcock, director of the FDA’s Center for Drug Evaluation and research. “While the FDA is willing to approve relatively toxic cancer drugs, it is done on the basis of the [drug’s] risks and benefits.”

“Given the number of serious and life-threatening events, we concluded that there was not a favorable risk-benefit profile in first-line therapy,” noted Richard Pazdur, MD, director of the FDA’s Office of Oncology Drug Products. He added that the recommendation to withdraw approval of bevacizumab for breast cancer was “disappointing for the FDA” as well as breast cancer patients.

“I want to assure breast cancer patients that there will be no disruption in treatment…and oncologists should use their medical judgment as to whether to continue treatment,” Woodcock emphasized. The FDA recommendation will have no immediate effect on approval or product labeling, and patients will have access to the drug until a final decision is made. Genentech, the drug’s maker, is requesting a hearing to review the recommendation.

Bevacizumab also is approved to treat colon, kidney, lung, and brain tumors and could be prescribed off-label to treat breast cancer if approval for that indication is withdrawn. However, insurers would likely stop paying for the drug if it loses approval. Bevacizumab costs around $8000 per month and is prescribed for 17,500 breast cancer patients each year.