Adding Avastin® (bevacizumab) to chemotherapy for early stage colon cancer didn’t reduce the risk that cancer would return.
In fact, preliminary results of the AVANT trial found that chemotherapy alone worked better in preventing recurrences of stage III and high-risk stage II colon cancer, according to a news release from Roche, sponsors of the international clinical trial.
This is the second trial in which adding Avastin to chemotherapy after surgery for early stage colon cancer failed to show a disease-free survival benefit. The C-08 trial found that, although Avastin did improve disease-free survival during the first year of treatment, the benefit had disappeared by the third year.
The results of the AVANT trial have been eagerly awaited since conclusions of the similar C-08 trial were announced in 2009.
After their surgery was over, the Phase III AVANT study randomly assigned 3,451 patients with stage III or high-risk stage II colon cancer to one of three arms:
- FOLFOX (continuous infusion 5-FU, leucovorin, and oxaliplatin) chemotherapy alone for 24 weeks, followed by observation for 24 weeks.
- FOLFOX plus Avastin for 24 weeks, followed by 24 weeks of Avastin alone.
- XELOX (oral Xeloda and oxaliplatin) in combination with Avastin for 24 weeks, followed by 24 weeks of Avastin alone.
The primary aim of AVANT was to find out if adding Avastin to standard chemotherapy improved the percentage of people alive without a cancer recurrence three years after treatment began (disease-free survival). Researchers also wanted to measure overall survival at five years and the safety of adding Avastin to chemo.
In announcing the AVANT results, Hal Barron, M.D., Head of Global Product Development and Chief Medical Officer at Roche, said.
While we originally hoped the significant survival benefit of Avastin seen in metastatic disease in colorectal cancer would be translated to the early setting, it is becoming increasingly clear that the effects of Avastin are different in the metastatic and early disease settings for patients with colon cancer.
Avastin is FDA approved to treat colorectal cancer that has spread beyond the colon or rectum (metastatic), where it does improve survival time.