Updated

The U.S. Food and Drug Administration has approved Eisai Corporation's Halaven as a treatment for metastatic breast-cancer patients who have received at least two prior chemotherapy regimens.

The FDA said the drug's safety and effectiveness were established in a study of 762 such patients receiving either Halaven or a different single-agent therapy chosen by their oncologist. Overall survival, the length of time from the start of treatment to the patient's death, was 13.1 months among the Halaven group, compared with 10.6 months for the others.

The most common side effects included a decrease in infection-fighting white blood cells, anemia, and a decrease in the number of overall white blood cells.

The drug is marketed by the Japanese pharmaceutical company's Eisai Inc. unit, which is based in Woodcliff Lakes, N.J. The FDA extended the drug's review in late August to address chemistry and other questions related to the "complex" manufacturing process involved in making Halaven.

Breast cancer is the second-leading cause of cancer-related death among women, according to the National Cancer Institute.

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