by Dr. C.H. Weaver M.D. updated 7/2019
In a pivotal phase III clinical trial, the addition of the targeted therapy Avastin® (bevacizumab) to chemotherapy, followed by maintenance therapy with Avastin was initially reported to slow cancer progression among women with advanced ovarian, primary peritoneal, or Fallopian tube cancer, however longer term follow did not demonstrate any overall survival benefit.(1,2)
Ovarian cancer has the highest mortality rate of all gynecologic cancers. It is the fifth leading cause of cancer death among U.S. women, with an estimated 21,550 new cases and 14,600 deaths in 2009.
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 the combination of Avastin and chemotherapy among women with ovarian cancer, researchers from the gynecologic oncology group conducted a phase III clinical trial among 1,873 women with newly diagnosed, advanced epithelial ovarian cancer, primary peritoneal cancer, or Fallopian tube cancer.
After surgery to remove as much of the cancer as possible, study participants were assigned to one of three treatment groups:
- Chemotherapy alone
- Chemotherapy plus Avastin with no maintenance therapy
- Chemotherapy plus Avastin followed by up to 10 months of Avastin maintenance therapy
Chemotherapy consisted of carboplatin and paclitaxel.
Maintenance therapy refers to ongoing treatment after the initial treatment is completed.
- Progression-free survival was initially reported to be 14.1 months among patients treated with chemotherapy plus Avastin followed by Avastin maintenance therapy, and 10.3 months among patients treated with chemotherapy alone.
Longer follow up however revealed no survival improvement in those treated with Avastin in addition to chemotherapy.(2) The median overall survival was 42.8 months for Avastin concurrent plus maintenance compared to versus 32.6 months for chemotherapy alone. In additon BRCA1/2, HRR, and CD31 were not found to be predictive of Avastin activity.
- Side effects of Avastin included high blood pressure and low white blood cell counts.
These results suggest that Avastin maintenance may initially slow cancer progression among women with advanced ovarian, primary peritoneal, or Fallopian tube cancer but the longer term benefit appears negligible.
- Burger RA, Brady MF, Bookman MA et al. Phase III trial of bevacizumab (BEV) in the primary treatment of advanced epithelial ovarian cancer (EOC), primary peritoneal cancer (PPC) or Fallopian tub cancer (FTC): A Gynecologic Oncology Group study. Presented at the 2010 annual meeting of the American Society of Clinical Oncology. June 4-8, 2010. Chicago, IL. Abstract LBA 1.
- J Clin Oncol. 2019 Jun 19. Epub ahead of print