Surprising results from two new studies may reopen debate about the value of Avastin for breast cancer. The drug helped make tumors disappear in certain women with early-stage disease, researchers found.
Avastin recently lost approval for treating advanced breast cancer, but the new studies suggest it might help women whose disease has not spread so widely. These were the first big tests of the drug for early breast cancer, and doctors were cautiously excited that it showed potential to help.
In one study, just over one third of women given Avastin plus chemotherapy for a few months before surgery had no sign of cancer in their breasts when doctors went to operate, versus 28 percent of women given chemo alone. In the other study, more than 18 percent on Avastin plus chemo had no cancer in their breasts or lymph nodes at surgery versus 15 percent of those on chemo alone.
A big caveat, though: The true test is whether Avastin improves survival, and it's too soon to know that -- both studies are still tracking the women's health. The drug also has serious side effects.
"I don't think it's clear yet whether this is going to be a winner," Dr. Harry Bear of Virginia Commonwealth University said of Avastin. But he added, "I don't think we're done with it."
Bear led one study, in the United States. Dr. Gunter von Minckwitz of the University of Frankfurt led the other in Germany. Results are in today's New England Journal of Medicine.
Avastin is still on the market for some colon, lung, kidney and brain tumors. In 2008, it won conditional U.S. approval for advanced breast cancer because it seemed to slow the disease. Further research showed it didn't meaningfully extend life and could cause heart problems, bleeding and other problems. The government revoked its approval for breast cancer in November.
Now doctors can prescribe Avastin for breast cancer but insurers may not pay. Treatment can cost $10,000 a month. The drug is made by California-based Genentech, part of the Swiss company Roche. It is still approved for treating advanced breast cancer in Europe and Japan.
The U.S. study was paid for by the National Cancer Institute with some support from drug companies. The German study was sponsored by drug companies. Some researchers consult for Genentech or other makers of cancer drugs.
Three other studies are under way testing Avastin in early breast cancer, said Dr. Sandra Horning, global development chief of cancer drugs for Roche and Genentech. The company does not plan to seek any change in Avastin's use until more results are available, she said.