Adding Bevacizumab to Vinorelbine, Platinum-Based Chemotherapy Improves Outcomes for Patients with HER2- Metastatic Breast Cancer

The addition of bevacizumab (Avastin; Roche) to the vinorelbine (Navelbine; Pierre Fabre Group) and platinum-based chemotherapy regimen demonstrated efficacy and safety in heavily pretreated human epidermal growth factor receptor 2-negative (HER2–) metastatic breast cancer (MBC) in a retrospective cohort study conducted at Taipei Veterans General Hospital in Taiwan. The researchers reported that the combination improved progression-free survival (PFS) by 4 months compared with the vinorelbine-platinum regimen alone.¹

Breat cancer cells | Image Credit: © Thipphaphone - stock.adobe.com

HER2 BCs are the most common BC subtype and can be particularly challenging to treat given the heterogeneity of the tumor microenvironment. The presence of overexpressed HER2 proteins drives tumor progression and encourages disease recurrence. Medical advancements have improved outcomes for patients; however, those with MBC continue to face poorer prognoses and have a 5-year survival rate of only 30%.^1,2

Angiogenesis is a key driver of the progression of MBC, and elevated serum levels of VEGF have been linked to poorer clinical outcomes. Bevacizumab is a VEGF-neutralizing antibody that plays a crucial role in inhibiting tumor angiogenesis. Prior meta-analyses have shown the clinical benefit of bevacizumab when combined with chemotherapy for patients with HER2– MBC. In the retrospective study, the authors aimed to determine the clinical and molecular effects of combining a bevacizumab and vinorelbine-platinum regimen for treatment of heavily pretreated HER2– MBC.¹

The study involved a total of 54 patients with HER2– MBC and treated with the vinorelbine-platinum regimen. The study population consisted entirely of female patients with a mean age of 57.2 ± 8.7 years. Hormone receptor status varied, with 64.8% (n = 35) being estrogen receptor and/or progesterone receptor-positive, whereas 35.2% (19 patients) had triple-negative BC. A significant proportion—over 60%—had metastatic involvement in the bone, lung, or liver, highlighting the advanced nature of the disease. All patients had prior treatment with anthracyclines and taxanes, and half had undergone greater than or equal to 5 lines of chemotherapy. At diagnosis, 37% (n = 20) presented with de novo metastatic disease, whereas the remaining 63% had recurrent disease.¹

The patients were assigned to receive the vinorelbine-platinum regimen with (n = 12) or without bevacizumab. The primary end points researchers measured were PFS, overall survival (OS), objective response rate (ORR), and disease control rate (DCR). They utilized RNA-sequencing, Cox regression analyses, and transcriptional profiling to determine the efficacy of the combination regimen.¹

Patients on the combination therapy achieved a median PFS of 2.3 months and an OS of 7.3 months, according to the authors. The addition of bevacizumab yielded a PFS improvement of 4.1 months (HR: 0.54, P = 0.04) and OS increased to 12.4 months. ORR and DCR were 11.1% and 27.7%, respectively, and were raised to 25% and 83.3% with bevacizumab. Notably, the median OS for hormone receptor-positive patients was 6.6 months, but the median OS for TNBC patients was 12 months, suggesting that patients with TNBC had a superior response to the treatment.¹

Among the participants, 11.1% achieved a partial response, 16.7% exhibited stable disease, and 72.2% demonstrated progressive disease, according to the authors. Adverse events occurred in 37% of patients, with no grade 4 events reported.¹

The findings suggest that the addition of the VGEF neutralizing capabilities of bevacizumab may provide patients with HER2– MBC an alternative therapeutic option to address tumor angiogenesis.

REFERENCES

Ho IW, Tseng YR, Liu CY, et al. Addition of bevacizumab to vinorelbine-platinum combination is efficacious in heavily pretreated HER2-negative metastatic breast cancer. J Cancer. February 11, 2025. doi: 10.7150/jca.105199

Ribociclib plus adjuvant endocrine therapy is safe, tolerable in patients with HR+/HER2– breast cancer. Pharmacy Times. January 31, 2025. Accessed February 27, 2025. https://www.pharmacytimes.com/view/ribociclib-plus-adjuvant-endocrine-therapy-is-safe-tolerable-in-patients-with-hr-her2-breast-cancer