Expert panel to probe safety of Avastin for Breast cancer

Avastin, a U.S. biotechnology company Genentech Inc.’s blockbuster cancer drug, doesn't seem to significantly lengthen the lives of women with breast cancer, and may increase the risk of death, the Food and Drug Administration said Monday in a review of the drug.

The fresh analysis by the federal agency’s staff shows that the breast cancer treatment drug Avastin failed to help patients with advanced breast cancer live longer, and had serious side effects, including cardiovascular problems, bowel perforations, and deaths.

The health regulator’s recent drug analysis dims the South San Francisco drug company’s chances to win approval for Avastin as a treatment for breast cancer.

The US health watchdog FDA said Monday that it would ask outside experts for a recommendation on whether Avastin should be approved to treat breast cancer.

An expert advisory panel is due to hold a meet on Wednesday in Gaithersburg, Maryland to discuss whether Avastin will win approval for breast cancer. Avastin is already a blockbuster drug for colon and lung cancer, and Genentech is seeking approval for advanced breast cancer in patients who haven't previously received treatment.

Avastin, the biotechnology company Genentech’s second biggest money maker, was first approved on 26th Feb, 2004 as a first line treatment for metastatic colorectal cancer, in combination with intravenous 5-FU based chemotherapy. The drug was also approved on 11th Oct, 2006 as the first line treatment of patients with locally advanced, recurrent or metatatic non-squamous, non-small cell, lung cancer.

Although FDA is not bound to follow its advisory panel's recommendations, it generally follows their guidance. The agency makes a decision on whether a product should be approved after evaluating all data and considering the recommendations of the advisory committee.

The expert panel would likely consider findings from study showing Avastin, also called bevacizumab, failed to show a major benefit in breast cancer patients who had already taken two chemotherapy drugs.

In a clinical trial, sponsored by the National Cancer Institute, the experts noted that Avastin slowed the spread of tumors compared with patients given only chemotherapy drug paclitaxal, a generic drug also sold as the branded treatment Taxol.

They found that adding Avastin to the drug paclitaxel though nearly doubled the time before tumors worsened, but the Avastin-chemotherapy combination did not appear to significantly improve the overall survival of patients.

In addition, Avastin along with chemotherapy caused some disturbing side effects, including hypertension, congestive heart failure and perforated bowels. According to the FDA report, 71 percent of the study participants who got Avastin suffered a serious side effect, compared with 51 percent of the women who got paclitaxel alone.

Among the serious side effects the worsened were the deaths of six women. In the study, six of the 363 patients, or 1.7 percent, who took Avastin died from side effects of the drug, compared with none of the 348 people on chemotherapy, the report stated.

FDA is expected to decide on whether to approve Avastin for breast cancer by Feb. 23, 2008.

Genentech fell $2.86, or 3.8 percent, to $73.39 at 4 p.m. in New York Stock Exchange trading on Monday.