Avastin, produced by Genentech, had full-fledged approval as a treatment for certain advanced cancers affecting the colon, lung, kidney and brain, based on thorough clinical trials. It got provisional approval for Avastin to treat metastatic breast cancer in 2008, based largely on a single trial. The trial found that when Avastin was added to a standard chemotherapy agent, it delayed the median time before cancers grew worse by five and a half months compared with the standard drug alone. It also found that Avastin did not prolong women’s lives and a small percentage of women suffered serious or potentially life-threatening side effects.
The F.D.A. has been trying to bring promising drugs for life-threatening diseases to market quickly while thorough studies are conducted to be sure they are safe and effective. In Avastin’s case, the answer was disappointing.
When Avastin was combined with two different chemotherapy drugs, it delayed progression of tumor growth by only one to three months and did not prolong lives or improve quality of life. It also caused a greater risk of serious adverse events than in the original trial. The F.D.A. and its advisory committees of experts have now concluded quite reasonably that such meager benefits did not justify the severe risks to some women.
The decision has been denounced by some conservatives as regulatory overkill that will impede progress and innovation in the fight against cancers. But, if the F.D.A. is going to allow innovative drugs on the market based on promising early studies, it must be able to revoke those approvals based on more definitive evidence.
"I did not come to this decision lightly," said FDA commissioner Dr. Margaret Hamburg. "Sometimes despite the hopes of investigators, patients, industry and even the FDA itself, the results of rigorous testing can be disappointing."
Avastin remains still on the market to treat colon, lung, kidney, and brain cancers, and doctors are free to prescribe it as they see fit. So even though Avastin's approval for breast cancer has been revoked, women could still get it - though their insurers may not pay for it. Including infusion fees, a year's treatment with Avastin can run $100,000.
The breast cancer organization Susan G. Komen for the Cure said it respected the FDA decision and that it was time for researchers to focus on finding so-called biomarkers that would tell which drug is right for which patient.
"Each type of cancer is very different from another in important ways, and in the end it's no surprise that Avastin's effectiveness may not be equivalent against all types of cancer," said Dr. Neal Meropol of University Hospitals Case Medical Center in Cleveland, who has long used Avastin for colon cancer.
But the ruling didn't sit well with some breast cancer patients who have been taking the drug.
"It's saved my life," said Sue Boyce of Chicago. The 54-year-old has taken Avastin since joining a research study in 2003. Her breast cancer eventually spread to her lungs, liver, and brain, but Boyce said she is faring well.
"So I'm hoping the insurance company will grandfather me in to continue taking it," she said.
The Avastin story began in 2008, when a study suggested the drug could delay tumor growth in breast cancer patients whose cancer had spread elsewhere in the body. Over the objection of its own advisers, FDA gave Avastin conditional approval - it could be sold for such women while its maker, Genentech, tried to prove it really worked.
Problem was, the antitumor effect proved to be smaller than first thought. Across repeated studies, patients given Avastin didn't live longer or have a higher quality of life. And the drug can cause severe high blood pressure, bleeding, heart attack or heart failure and tears in the stomach and intestines, the FDA concluded.
Genentech had argued the drug should remain available while it conducted more research to see if might help certain breast cancer patients. Some patients and their doctors had argued passionately for the drug.
"There certainly are patients who benefit tremendously," said Boyce's oncologist, Dr. Melody Cobleigh of Rush University Medical Center. "We'll just be battling with the insurance companies."
"For those not fortunate enough to be on (a government health plan) or an insurance plan that covers it, it's a death sentence," Christi Turnage of Madison, Miss., said of the FDA decision. Her breast cancer had moved into her lungs before she began Avastin three years ago and the spreading stopped, but Turnage said her insurer is ending coverage and she will seek financial help from Genentech.
Hamburg said she considered those arguments but that researchers hadn't found any clues to identify who those rare Avastin responders would be. She urged Genentech to do that research, saying the FDA "absolutely" would reconsider if the company could find the right evidence.
Tags: 2 new breast cancer drugs, Breast cancer patients, Bone drug breast cancer,
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