U.S. drug regulators Friday withdrew approval of Roche's Avastin as a treatment for breast cancer, capping a protracted and emotional battle over a drug backed by many survivors of the disease.

U.S. Food and Drug Administration Commissioner Margaret Hamburg said Avastin has not proven safe and effective for breast cancer. The drug will remain on the market for other uses, such as treating types of colon, lung, kidney and brain cancer.

Advisers to the FDA paved the way for Friday's decision, recommending against Avastin's use in breast cancer in June. The panel, convened after Roche appealed the FDA's original plan to revoke the breast cancer indication, heard emotional testimony from patients who insisted that Avastin had saved their lives.

Some insurers have already started pulling back on Avastin coverage for breast cancer. Without FDA approval, women worry they will not have access to the expensive drug.

Using Avastin for metastatic breast cancer costs about $88,000 a year, based on patients taking it for 11.3 months, Roche said.

It remains unclear whether government insurance programs will also change their coverage of Avastin. In June, the Centers for Medicare and Medicaid told Reuters that Medicare would continue paying for Avastin for breast cancer regardless of the FDA's final decision.

``We are disappointed with this outcome,'' said Charlotte Arnold, a spokeswoman for Genentech, a unit of Roche. ``We remain committed to the many women with this incurable disease and will continue to provide help through our patient support programs to those who may be facing obstacles to receiving their treatment.''

She said Roche will pursue a new Phase III study of Avastin in combination with the chemotherapy drug paclitaxel in previously untreated metastatic breast cancer.

The FDA's decision could prompt a review of industry guidelines from groups like the National Comprehensive Cancer Network, which represents leading cancer treatment centers.

NCCN has so far not strayed from its earlier guideline, approving use of Avastin with paclitaxel for some patients.