Efficacy and safety of eribulin plus gemcitabine as second-line treatment for recurrent HER2-negative breast cancer: a phase II, single-arm, open-label trial.

[BACKGROUND] Eribulin plus gemcitabine improves progression-free survival in chemotherapy-naive metastatic breast cancer patients, but its efficacy in second-line or later treatment remains unclear.

[METHODS] This single-arm, phase II study was conducted at 13 Chinese medical centers. Eligible patients had histologically confirmed human epidermal growth factor receptor 2 negative metastatic breast cancer and had received at least one prior taxane-containing chemotherapy regimen and anthracycline-containing regimens in the adjuvant setting. Patients received intravenous infusions of eribulin (1.4 mg/m) and gemcitabine (1.0 g/m) on days 1 and 8 of a 21-day cycle. Progression-free survival, objective response rate and disease control rate were assessed. Adverse events were also recorded.

[RESULTS] Here we show 70 patients took part in this study (71.4% hormone receptor positive/HER2 negative). Patients had received a median of three prior lines of systemic treatment. Overall, 48.6% have significant tumor shrinkage, 92.9% have tumor control, and median time without disease progression is 7.2 months (95% confidence interval, 5.5-10.9). Median time without disease progression is 8.4 months (hormone receptor positive) vs. 6.3 months (triple-negative, p = 0.1849). Grade 3-4 side effects mostly affect blood cells and are manageable.

[CONCLUSIONS] Eribulin plus gemcitabine is effective and well-tolerated in patients with HER2-negative metastatic breast cancer needing second-line or later treatment, providing a valuable treatment option.