A new drug derived from chemicals in marine sponges may help to extend the lives of patients with advanced breast cancer, according to the results of a recent phase-III trial.

Eribulin, brand name Halaven, is a new chemotherapy drug that binds microtubules - structures that form the scaffolding that allows cell division - in a different way to existing chemotherapy drugs.

By binding these microtubules, the new drug may help to prevent cells from dividing and cause them to self-destruct.

Scientists at the Vall d'Hebron Institute of Oncology in Barcelona and the University of Leeds carried out the phase-III 'EMBRACE' trial of eribulin, which involved 762 women, all of whom had failed to respond to aggressive treatment with other therapies.

Of these, 508 patients were given eribulin, while the remaining 254 used a standard treatment recommended by their doctor.

Women who took eribulin lived for a median of 13.1 months, while those on standard treatments survived for a median of 10.6 months.

Weakness and fatigue were more common among eribulin users than those on standard therapies - 54 per cent versus 40 per cent. Also more common was a depletion of white blood cells - 52 per cent versus 30 per cent.

Five per cent of eribulin users stopped taking the drug because of numbness or pain.

Writing in the Lancet medical journal, Cancer Research UK scientist Professor Chris Twelves, from the University of Leeds, and colleagues concluded: "This global phase-III study establishes a potential new standard treatment for women with heavily pre-treated metastatic breast cancer, for whom there was previously no chemotherapy treatment with proven survival benefit."

Lead author Dr Javier Cortes, a specialist oncology physician at Vall d'Hebron University Hospital, said: "There is an urgent need for therapies with a proven survival benefit for women with metastatic breast cancer who have already received multiple treatments.

"In the EMBRACE study we see a clear overall survival benefit for these patients when treated with Halaven. This is a remarkable step forward in this treatment setting where previously, overall survival has been considered an endpoint difficult to attain."

The study authors also suggested that future studies should look at the possible benefits of eribulin in women with earlier stages of breast cancer.

Eribulin has not yet receiving marketing authorisation in Europe, but was approved by the US Food and Drug Administration in November 2010.

Dr Julie Sharp, senior science information manager at Cancer Research UK, said: "This trial shows that it is possible to improve survival for women with advanced breast cancer, even after multiple treatments - and researchers will build on these results to increase the options for women in the future."

Source: CRUK

Article: Cortes J et al: Eribulin monotherapy versus treatment of physician's choice in patients with metastatic breast cancer (EMBRACE): a phase 3 open-label randomised study, Lancet 2011 10.1016/S0140-6736(11)60070-6