WASHINGTON (AP) — The blockbuster drug Avastin should no longer be used in advanced breast cancer patients because there's no proof that it extends their lives and it presents dangerous side effects, the government declared Friday.

The ruling by the Food and Drug Administration was long expected, but it was certain to disappoint women who say they've run out of other options as their breast cancer spread through their bodies. Impassioned patients had lobbied furiously to preserve Avastin as a last shot.

"This was a difficult decision," said FDA Commissioner Margaret Hamburg. But, she added that "it is clear that women who take Avastin for metastatic breast cancer risk potentially life-threatening side effects without proof that the use of Avastin will provide a benefit, in terms of delay in tumor growth, that would justify those risks."