By administering bevacizumab 1 day before etoposide and cisplatin, the BEEP (bevacizumab, etoposide, cisplatin) regimen may be highly effective in patients with brain metastases of breast cancer who are refractory to whole-brain radiotherapy (WBRT), a study published in the journal Clinical Cancer Research has shown.
For the single-arm, phase II study, researchers sought to assess whether a window period between bevacizumab and cytotoxic agents may enhance drug delivery into tumor tissue in patients with brain metastases of breast cancer.
Researchers enrolled 35 patients with brain metastases of breast cancer who were refractory to WBRT. Patients received bevacizumab 15mg/kg on day 1, etoposide 70mg/m2/day on days 2-4, and cisplatin 70mg/m2 on day 2 in 21-day cycles. Patients received a maximum of six cycles.
Results showed that 77.1% (95% CI: 59.9 – 89.6) of patients achieved a central nervous system (CNS)-objective response, including 13 patients who had at least an 80% volumetric reduction of CNS lesions.
Researchers found that with a median follow-up of 16.1 months, the median CNS progression-free survival was 7.3 months (95% CI: 6.5 – 8.1) and the median overall survival was 10.5 months (95% CI: 7.8 – 13.2).
In regard to safety, the most common grade 3 or 4 toxicities were neutropenia and infection.
The researchers note that further study of bevacizumab-induced vascular normalization window concept is warranted before this regimen is used in this patient population.