Eribulin combined with antiangiogenic agents in women with HER2-negative metastatic breast cancer: a retrospective multicenter study

Background: The relative lack of specifically targeted agents for HER2-negative metastatic breast cancer (MBC) makes the need for new agents or combination therapies to maximize clinical benefit while reducing toxicity critical.Objectives: To retrospectively analyze the efficacy and safety of eribulin combined with antiangiogenic drugs in the treatment of Chinese women with HER2-negative MBC.Methods: A total of 85 consecutive MBC patients with HER2-negative who were treated with eribulin + antiangiogenic agents between October 2020 and April 2023 in four institutions were retrospectively included in this study. Patients received eribulin 1.4 mg/m2 (day 1 and 8) plus bevacizumab 7.5 mg/kg (day 1, 64 patients) or anlotinib 10 mg daily (day 1-14, 16 patients) or apatinib 250 mg daily (5 patients) on a 21-day cycle until progression or unacceptable toxicity. The primary end-point was progression-free survival (PFS), according to Response Evaluation Criteria in Solid tumors (RECIST) 1.1. Secondary end-points included toxicities, objective response rate (ORR), disease control rate (DCR), and overall survival (OS). Adverse events (AEs) were graded according to Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.Results: The study included 85 HER2-negative MBC patients, with 41 patients (48.2%) in the first to second line group and 44 patients (51.8%) in the greater than or equal to third line group. The median age was 54.0 years. Thirty patients in the first to second line group and 14 patients in the greater than or equal to third line group had triple-negative breast cancer (TNBC). The ORR and DCR were 34.1% (29/85) and 75.3% (64/85). The median PFS (mPFS) of total population was 6.0 months (95% CI: 4.3-7.7), and median OS (mOS) was immature. The mPFS was 7.7 and 4.3 months in the first to second and greater than or equal to third line treatment (p = 0.003), respectively. TNBC patients in first to second line therapy showed a significantly longer PFS (6.5 months versus 2.0 months, p = 0.021) compared to greater than or equal to third line. The incidences of cardiovascular toxicity were 29.4% in grades 1-2 and no grades 3-4. Hematologic toxicity (leukopenia and neutropenia) was the most common grade >= 3 AEs, and AEs were more common in patients in greater than or equal to third line.Conclusion: The results suggest that eribulin combined with antiangiogenic therapy has a meaningful clinical activity and an acceptable safety profile in HER2-negative MBC.