A drug called eribulin could help extend the lives of women with the most advanced forms of breast cancer by at least two months, new research suggests. The drug mimics the behaviour of a compound naturally found in sea sponges.

Although it’s not a cure, research presented at the National Cancer Research Institute in Liverpool, UK, has revealed that women with advanced triple negative breast cancer can live for an average of five extra months when taking the drug.

The drug is already being used to treat women who have previously undergone two rounds of chemotherapy, but this is the first time it's been tested as an earlier form of treatment. It's now passed Phase III clinical trials, which is the last step before a drug is released onto the market.

The incredible results are taken from two major clinical trials involving more than 1,800 women with breast cancer that had already started spreading to other parts of the body - a process known as metastasis.

Metastasis is responsible for around 90 percent of all cancer deaths and, once it’s occurred, breast cancer patients only have around a one in 10 chance of living for 10 years. If the cancer hasn’t spread, patients now have a nine in 10 chance of surviving for a decade.

The studies showed that, overall, eribulin can help women with breast cancer survive two months longer than those receiving regular treatment. But in the groups of women who had the advanced triple negative form of breast cancer, which has limited treatment options available, these women survived for nearly five months longer they did without the drug.

"Eribulin has previously been offered to women who've already been through several lines of chemotherapy. But the European Union has recently approved eribulin for patients who have received less treatment for their breast cancer, which means we hope to give more patients another treatment option in the not-too-distant future,” said Chris Twelves, an oncologist based at the University of Leeds in the UK who led the research, in a press release.

Eribulin works by stopping the cancer cells from dividing by inhibiting microtubules - structures in the cell that are involved in mitosis, when one cell splits into two. Eribulin was originally taken from a molecule called Halichondrin B, which nautrally occurs in a species of sea sponge called Halichondria okadai (not pictured above), but now it’s produced in the lab.

"These results are encouraging and may offer valuable extra time to patients whose cancers have stopped responding to conventional treatments and have few options left. Advanced breast cancer can be very difficult to treat so these results take us a small, important step in the right direction,” said Martin Ledwick, the head information nurse at Cancer Research UK, in the release.

"Although eribulin isn't a cure, it's an extra treatment option for patients with advanced breast cancer, which can be priceless to them and their families."