Bevacizumab with chemotherapy as a third-line treatment for recurrent/metastatic breast cancer

This study investigated the long-term effectiveness bevacizumab (Avastin) with chemotherapy for HER2-negative locally recurrent/metastatic breast cancer. This study concluded that while bevacizumab combined with chemotherapy significantly improved time to disease progression compared with chemotherapy alone in the first two phases of the trial, there was no benefit in using bevacizumab a third time. 

Bevacizumab is a treatment that slows the growth of new blood vessels, which tumors need for growth. Previous studies have shown that bevacizumab combined with chemotherapy can improve the time to disease progression in patients with locally advanced or metastatic (spread) breast cancer. One trial noted that bevacizumab plus chemotherapy had improved progression-free survival on average by 6.3 months, compared to 4.2 months with chemotherapy treatment alone. 

Bevacizumab has been found to be effective as a first and second-line treatment. It is not clear whether it improves survival in patients who have progressed following two prior rounds of bevacizumab treatment.

The study originally included 494 patients. Of those, 483 patients received second-line treatment. 234 patients continued to phase III of the treatment. The average duration of treatment with bevacizumab in this study was 2.1 months. The average follow-up time was 32.1 months in the chemotherapy group, and 30.9 months in the bevacizumab plus chemotherapy group.

There was no significant difference in progression-free survival or in overall survival between the two treatment groups.

23% of patients treated with bevacizumab experienced protein in the urine (a marker for kidney function). This was compared to 13% in the chemotherapy group. 20% of the bevacizumab group experienced high blood pressure, compared to 4% of the chemotherapy group.

The study concluded that bevacizumab as a third-line treatment does not appear to improve outcomes further.