Eribulin is an active and well-tolerated therapy for women with metastatic breast cancer (MBC) receiving this therapy as a first-, second-, or third-line chemotherapy regimen, though eribulin is not superior to capecitabine. These findings, from an international research team, were published in the Journal of Clinical Oncology (2015; doi:10.1200/JCO.2013.52.4892).

In addition, these patients had all been previously treated with both an anthracycline and a taxane in either the adjuvant or metastatic setting. This study is the first to address the use of eribulin early in the course of metastatic breast cancer, specifically either the first- or second-line setting.

“Additionally, it is of great interest that subset analysis suggests that eribulin may be particularly active and effective in triple negative MBC, which is known to be an aggressive subset of breast cancer, and one associated unfortunately with a particularly poor prognosis overall,” said lead researcher Peter A. Kaufman, MD, of the Norris Cotton Cancer at Dartmouth-Hitchcock Medical Center in Lebanon, New Hampshire.

Eribulin has been approved in numerous countries in the third line or latter setting for the treatment of MBC, and is increasingly widely used. It is the only chemotherapeutic agent shown to have a survival benefit for patients with MBC in the third line or latter chemotherapeutic setting. Given previous research findings, and now findings from this large international trial, there has been great interest from oncologists and other clinicians in the potential impact that eribulin might have earlier in the course of MBC.

This phase III randomized trial (ClinicalTrials.gov identifier NCT00337103) assigned 1,099 women who had previously been treated with an anthracycline or a taxane to either eribulin or capecitabine as their first-, second-, or third-line chemotherapy for advanced MBC. Stratification factors were human epidermal growth factor receptor-2 (HER2) status and geographic region. Co-primary end points were overall survival and progression-free survival.

“While there is not a statistically significant difference in overall survival with eribulin in comparison to capecitabine, the median overall survival seen with eribulin is in fact numerically slightly superior to that of capecitabine,” explained Kaufman.

This work supports, and has in part led to, a number of further studies of eribulin in breast cancer. Plans are underway to proceed with pilot adjuvant and neoadjuvant studies, and further studies in MBC.

“We are currently developing further studies evaluating the utility of eribulin in treating women with triple negative disease, either alone, or in combination regimens with other therapies,” Kaufman commented. “We are additionally planning further research evaluating the role of eribulin in other subtypes of breast cancer, particularly in early stage breast cancer, where this therapy may in fact have a great impact, and improve the cure rate for early stage disease.”

This study was supported by EISAI Pharmaceuticals.