Taxanes have been shown to be the most effective treatment for recurrent or metastatic breast cancer. However, for patients pretreated with taxanes, more active and possibly less toxic drugs are needed. In this retrospective study, we investigated on the effectiveness and safety of eribulin mesylate in 91 taxane-refractory subjects, extracted from the ESEMPIO database, which included 497 metastatic breast cancer patients treated with eribulin allover the Italy. This analysis included only those patients who have shown disease progression while receiving taxane therapy (primary refractory), or those who achieved a response followed by progression while still on therapy (taxane failure). Overall, 41/91 patients (45.2%) showed a clinical benefit; 1 complete response (2.2%) and 16 partial responses (17.6%) were observed. The median progression free survival was 3.1 months (95% CI: 2.8–3.5) and the median overall survival was 11.6 months (95% CI: 8.7–16.7). With regard to toxicity, 53 patients (58%) experienced asthenia/fatigue, 23 (25%) showed peripheral neurotoxicity, 18 (20%) alopecia, 12 (13%) mild constipation and 27 (30%) neutropenia. The toxicity related to the treatment led to eribulin dose reduction in 19 (21%) and discontinuation in 9 (10%) patients, respectively. In conclusion, this study suggests that eribulin is effective and well tolerated also in taxane-refractory patient.
