Breast Cancer Drug Eribulin Extends Survival

March 2, 2011 -- The new breast cancer drug eribulin (Halaven) extends survival two and a half months longer than other therapies for advanced breast cancer, researchers report.

''This will rapidly emerge as the standard tried-and-tested option," researcher Chris Twelves, MD, PhD of St. James University Hospital in the U.K., tells WebMD.

The new chemotherapy drug, approved in November by the FDA, was compared to existing treatments typically offered to women who have locally recurrent breast cancer or breast cancer that has spread despite up to five previous regimens of chemotherapy, Twelves says.

''There was a significant prolongation of survival in the group of women who received eribulin," he tells WebMD.

Those on eribulin lived a median of 13.1 months (half survived longer, half less) compared to a median survival time of 10.6 months for women treated with other therapies.

While the increase may not seem like much, Twelves says, it may allow women to enjoy life milestones such as anniversaries, birthdays, and graduations.

"I need to emphasize this isn't curative treatment," Twelves says. His team's intent was to compare overall survival, challenging the common wisdom that improving overall survival in this group of women is unrealistic.

The role of the treatment, he says, is to extend survival a bit longer when other treatment options have failed.

The study is published in The Lancet. Twelves consults for Eisai Inc., which makes the drug and funded the trial.

Comparing Breast Cancer Treatments

In the study, known as the EMBRACE trial, Twelves and his colleagues randomly assigned 762 women either to the new drug or to the treatment chosen by their doctors as predicted to have the best effect. The assignments were made from late 2006 to late 2008 and involved patients from 135 centers in 19 countries.

Of those 762 women, 508 received eribulin and 254 received their doctor’s treatment choice. That could be either chemotherapy with a single agent, biological or hormonal treatment, radiotherapy, or supportive care. None got supportive care alone, and most, 96%, got chemotherapy.

The eribulin was administered intravenously for two to five minutes on days one and eight of a 21-day cycle. The median duration of treatment was about four months. For the other group, the median length of treatment ranged from about one to two months.

The researchers wanted to look primarily at overall survival between the two groups. The 2.5-month difference with eribulin was significant, they found.

They also found that nearly 54% of the eribulin group and 43% of the other group survived a year.

When they looked at progression free survival -- those women who survived but also did not have cancer progression -- they found the median was 3.7 months for those on eribulin and 2.2 months for those on other treatments.