Evaluating continuation of bevacizumab plus chemotherapy in patients with metastatic colorectal cancer after disease progression

This article evaluated the use of bevacizumab alongside chemotherapy in patients with metastatic colorectal cancer after the progression of the disease following treatment with bevacizumab.

Cancer cells need blood supply in order to grow. They do so by forming new blood vessels thereby feeding themselves. Bevacizumab (Avastin) is a biological therapy (a treatment that helps the patient’s immune system to fight cancer) drug for the treatment of some types of metastatic cancer, including colorectal cancer. It works by stopping the growth of new blood vessels of the cancer, thereby slowing the progression of cancer. Metastatic colorectal cancer is cancer that has spread from the large intestine to other tissues and organs. These patients are usually treated with chemotherapy plus biological therapy. However, there is no clear data on how to treat patients whose cancer has progressed after treatment. 

This study included 820 patients with metastatic colorectal cancer. All of these participants had already been treated with bevacizumab and chemotherapy and had disease progression in the first 3 months after finishing treatment. Following this progression of their cancer, 411 patients were randomly assigned to receive chemotherapy alone and 409 patients were treated with chemotherapy plus bevacizumab.

After approximately 1 year of follow up, patients who received bevacizumab in addition to chemotherapy treatment had an overall survival (defined as the time patients survived since treatment) of 11.2 months compared to 9.8 months in patients treated with chemotherapy alone. However, more patients treated with bevacizumab experienced side effects compared to those treated with chemotherapy alone. These side effects included increased risk of infections, diarrhea and physical weakness. 

In summary, this study showed that patients with metastatic colorectal cancer who continued bevacizumab treatment along with chemotherapy after the cancer has progressed had improved survival compared to patients treated with chemotherapy alone.