The addition of the targeted drug Avastin® (bevacizumab) to chemotherapy may improve outcomes among women with newly diagnosed or recurrent ovarian cancer. These results—from two Phase III clinical trials—were presented at the 2011 annual meeting of the American Society of Clinical Oncology.
Treatment for ovarian cancer commonly involves surgery and/or chemotherapy. Outcomes for women diagnosed with advanced disease remain poor, and researchers continue to evaluate new approaches to treatment.
Avastin is a targeted therapy that blocks a protein known as VEGF. VEGF plays a key role in the development of new blood vessels. By blocking VEGF, Avastin deprives the cancer of nutrients and oxygen and inhibits its growth. Avastin has been approved for the treatment of selected patients with breast cancer, lung cancer, colorectal cancer, kidney cancer, or glioblastoma.
To evaluate Avastin among women with recurrent ovarian, peritoneal, or fallopian tube cancer, researchers conducted a Phase III clinical trial (the OCEANS study) among 484 patients with platinum-sensitive disease. Study participants were treated with chemotherapy (carboplatin and gemcitabine) in combination with either Avastin or a placebo. After chemotherapy was completed, patients continued to receive Avastin or a placebo until cancer progression.
- Avastin delayed cancer progression. Progression-free survival was 12.4 months in the Avastin group and 8.4 months in the group that received chemotherapy alone.
- Response rate was also improved with Avastin: tumor shrinkage occurred in 79% of women in the Avastin group and 57% of women treated with chemotherapy alone.
In a prepared statement, the lead author of the study noted “The data from OCEANS demonstrate a clear response from [Avastin] in these cancers. These are very meaningful results for patients for whom there are currently limited treatment options available.”
In a second study, researchers evaluated Avastin in the treatment of newly diagnosed ovarian cancer that had a high risk of recurrence. The Phase III ICON7 study enrolled 1,528 women with high-risk or advanced epithelial ovarian, primary peritoneal, or fallopian tube cancer. Study participants were treated with chemotherapy with or without Avastin. Women in the Avastin group continued Avastin treatment after chemotherapy was completed.
- Overall, the Avastin group had a 15% reduction in risk of death (178 deaths in the Avastin group versus 200 in the chemotherapy-alone group). This difference between study groups did not meet the criteria for statistical significance, suggesting that it could have occurred by chance alone.
- In the subgroup of women at highest risk of recurrence, Avastin reduced the risk of death by 36% (79 deaths in the Avastin group versus 109 in the chemotherapy-alone group). This result was statistically significant, which suggests that it’s unlikely to have occurred by chance alone.
In a prepared statement, the lead author of the study concluded “It’s too early to reach firm conclusions about the full extent of the overall survival benefit of adding [Avastin] to the treatment regimen for newly diagnosed ovarian cancer, but it does seem very promising, particularly for patients at high risk of recurrence. We don’t have complete answers to all our questions today; we will have to wait for final results of the trial which are expected in about two years.”
 Aghajanian C, Finkler NJ, Rutherford T et al. OCEANS: A randomized, doubled-blinded, placebo-controlled, phase III trial of chemotherapy with or without bevacizumab (BEV) in patients with platinum-sensitive recurrent epithelial ovarian (EOC), primary peritoneal (PPC), or fallopian tube cancer (FTC). Paper presented at: 2011 Annual Meeting of the American Society of Clinical Oncology; June 3-7, 2011; Chicago, IL. Abstract LBA5007.
 Kristensen G, Perren T, Qian W et al. Result of interim analysis of overall survival in the GCIG ICON7 phase III randomised trial of bevacizumab in women with newly diagnosed ovarian cancer. Paper presented at: 2011 Annual Meeting of the American Society of Clinical Oncology; June 3-7, 2011; Chicago, IL. Abstract LBA5006.