Efficacy and safety of eribulin mesylate in patients with locally advanced or metastatic breast cancer previously treated with anthracycline/taxanes

Abstract Background This prospective real‐world study aimed to assess the efficacy and safety of eribulin in the clinical practice against advanced breast cancer (ABC) in China. Patients and Methods In this study, eligible patients with inoperable locally advanced or metastatic breast cancer who had experienced prior neo−/adjuvant or failed the palliative treatment with anthracycline/taxanes were included. Eribulin (1.4 mg/m 2 ) was infused intravenously on Day 1 and Day 8 every 3 weeks until disease progression or intolerable toxicity occurred. The progression‐free survival (PFS), overall response rate (ORR), disease control rate (DCR), and safety of the treatment were assessed. Results One hundred and thirty‐four patients were enrolled. The median PFS (mPFS) was 4.3 months (95% CI: 0.3–15.4). The ORR and DCR was 32.1% and 79.1%, respectively. The mPFS of patients who received eribulin as first‐ or second‐line treatment was significantly better than those who received eribulin as ≥3‐line treatment (6.9 months 95% CI: 3.2–8.8 vs. 4.0 months 95% CI: 3.4–4.6, p = 0.006). The mPFS of patients with triple‐negative, HER2‐positive, and HER2(−)/HR(+) was 3.4 (95% CI: 2.7–4.1), 6.2 (95% CI: 2.3–10.1) and 5.0 months (95% CI: 4.1–5.9), respectively. HER2(+) patients had significantly longer PFS than TNBC patients ( p = 0.022). Patients received combination therapy had a significantly longer mPFS than those who received eribulin monotherapy (5.0 months 95% CI 3.6–6.3 vs. 4.0 months 95% CI: 3.3–4.7 p = 0.016). Multivariate analysis revealed that MBC patients with a molecular typing of non‐TNBC receiving eribulin as ≤2‐line therapy and combination therapy had a low risk of disease progression. Neutropenia (33.58%), leukopenia (11.94%), and thrombocytopenia (4.48%) were the most common treatment‐related adverse events. Conclusion Eribulin demonstrated effective clinical activity and a favorable tolerability profile in Chinese patients with ABC in the real‐world. The efficacy and safety profile were consistent with those reported in previous randomized phase 3 trials.