Background and importance Eribulin is used, as monotherapy, in the secondline treatment of locally advanced or metastatic breast cancer (mBC) in patients who have previously received an anthracycline and a taxane or these are contraindicated.

ESMO-MCBS scores eribulin as level 2 (low clinical benefit) according to the EMBRACE study (Cortes et al, 2011). Results in a non-controlled setting are usually worse than those obtained in clinical trials.

Aim and objectives We aimed to assess progression free survival (PFS) and safety of eribulin in clinical practice.

Material and methods An observational, retrospective and descriptive study was conducted. Patients with mBC treated with eribulin between April 2014 and May 2019 were included. Age, HER-2 and hormone receptor status, previous regimens for metastatic disease, number of eribulin cycles and time to progression or death were collected. Treatment related adverse events were also analysed.

Thirty-four patients were included Median age was 54.1 (IQR 19.2) years; 82% were HER-2 negative and the other 82% were hormone receptor positive. Half (56%) of the patients had received three or more previous regimens. Median eribulin cycles was 5 (IQR 4.3). Median PFS was 3.5 months (IQR 4.2).

Fourteen patients (41.2%) suffered side effects, mainly neutropenia (20.6%), asthenia (14.7%), mucositis (11.8%), hepatotoxicity (8.8%), peripheral neuropathy (5.9%) and thrombocytopenia (5.9%).

Conclusion and relevance The benefit in PFS reported in the pivotal clinical trial was maintained in clinical practice. Adverse events were consistent with those reported in the EMBRACE study although the incidence was lower.

References and/or acknowledgements 1. Cortes J, O’Shaughnessy J, Loesch D, 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;377:914–923.

No conflict of interest.