The FDA has declared the drug Avastin no longer be used to treat breast cancer.
The FDA says Avastin causes dangerous side effects and it is unlikely it extends the lives of those who are fighting breast cancer.
Friday's ruling was long expected but is sure to disappoint women who say they have run out of other options.
The FDA commissioner says it was a difficult decision but patients must have confidence that drugs are effective.
Avastin will not stop selling as it is also used to treat colon cancer and certain other tumors. However, the FDA ruling is expected to influence insurance coverage.
Medicare says it will continue to cover Avastin while it evaluates whether a change is needed.