In Second Trial, Avastin Is Found Effective in Treating Breast Cancer

Genentech said Tuesday that a new clinical trial had shown that its best-selling drug Avastin was effective in treating breast cancer, a finding that could increase the chances that the product will be approved for that use.
The company said in an announcement after the close of trading that the trial showed that Avastin lengthened the time before the cancer worsened. Genentech’s shares rose 2.4 percent, to $71.60, in after-hours trading.

The Food and Drug Administration is scheduled to decide by Feb. 23 whether to approve Avastin for use in treating breast cancer. The decision is being closely watched as a barometer of the agency’s standards toward approving new cancer drugs or expanding uses of current medications. It is possible the F.D.A. will delay the decision past February so it can consider the new data.

Avastin, also known as bevacizumab, is already approved in the United States as a treatment for colorectal and lung cancers. Genentech sold $2.3 billion worth of Avastin in 2007, all in the United States. An agency advisory committee voted 5 to 4 in December that Avastin should not be approved for breast cancer.

The committee, basing its conclusions on a separate study, said the drug’s effectiveness in slowing the progression of the disease did not outweigh the drug’s toxic side effects, especially since women getting Avastin did not live significantly longer.

One concern of the F.D.A. staff and of the advisory committee was the difficulty the trial had in measuring precisely when cancer started to progress, or worsen.

The initial clinical trial of Avastin that was under discussion was conducted by an academic group without some of the procedures in place that the F.D.A. would have liked.

The new trial, however, was conducted by Roche, which owns a majority of Genentech and sells the drug overseas. The trial is thought to have had in place the controls the F.D.A. sought.

Also, the fact that the new trial showed that the drug slowed cancer progression might allay concerns that the first trial’s results were somehow a fluke. The results of the new trial, called Avado, came weeks earlier than expected.

“Genentech believes that the results of the Avado study provide confirmation of Avastin’s efficacy and safety in this patient population health club,” the company said in a statement.

While the new trial increased the period before breast cancers became worse, the study has not yet run long enough to show whether Avastin lengthens lives, which is considered the gold standard for a cancer drug. Michael Aberman, an analyst with Credit Suisse, said in a note to clients Tuesday that without survival data the new trial would not increase the chance for Avastin’s approval this month.

Genentech’s stock has been falling for the last two years because of investor concerns that the company’s once-meteoric growth was slowing. So extending Avastin to breast cancer treatment is considered important for the company.

Genentech did not provide any numerical results for the new trial, saying those would be presented at a medical meeting in the coming months. It said there were no new safety problems observed in the trial.

The trial tested Avastin as an initial treatment for women whose cancer had recurred or spread beyond the breast health club, the same type of patients as in the first trial. All 736 patients in the Avado trial received a separate chemotherapy drug, docetaxel. Some of the patients also got Avastin while others got a placebo.