Results from the OCEANS Study, a phase III study evaluating bevacizumab (Avastin?, F. Hoffmann-La Roche Ltd) in combination with chemotherapy (carboplatin and gemcitabine) followed by continued use of bevacizumab alone until disease progression in women with previously treated (recurrent), platinum-sensitive ovarian cancer, met its primary endpoint.
OCEANS is a multicentre, randomized, double-blind, placebo-controlled phase III study in 484 women with platinum-sensitive recurrent ovarian, primary peritoneal or fallopian tube cancer. Women in OCEANS had received no more than one treatment regiment prior to enrolment in the trial. The trial was designed to evaluate bevacizumab (15mg/kg every three weeks) in combination with carboplatin and gemcitabine chemotherapy, followed by bevacizumab as a single agent until disease progression, compared to placebo in combination with carboplatin and gemcitabine chemotherapy, followed by placebo alone. The primary endpoint of the study was progression-free survival. The secondary endpoints of the study included overall survival, objective response, duration of response and safety.
The study showed that women who received a combination of bevacizumab and chemotherapy followed by the continued use of bevacizumab alone, lived longer without their disease worsening (progression-free survival or PFS), compared to women who received chemotherapy alone. No new safety findings were observed and adverse events were consistent with those seen in previous pivotal trials of bevacizumab. Full data from the OCEANS study will be submitted for presentation at an upcoming medical meeting.
The time between receiving the last dose of platinum-based chemotherapy and disease recurrence is used to help determine the choice of chemotherapy used in the next line of treatment. Patients are said to have ?platinum-sensitive? disease if disease recurrence occurred more than six months after completing their initial platinum-based chemotherapy, and ?platinum-resistant? disease if recurrence occurred within six months.
Ovarian Cancer Ovarian cancer is the sixth most commonly diagnosed cancer in women and the eighth leading cause of cancer death among women worldwide. Annually, an estimated 230,000 women will be diagnosed with ovarian cancer around the world and approximately 140,000 will die from the disease . Surgery to remove as much of the tumour as possible is a mainstay of treatment but unfortunately, the majority of patients are diagnosed with late stage disease (when the cancer has grown or spread) and they require further treatment.
Ovarian cancer is associated with high concentrations of vascular endothelial growth factor (VEGF), a protein associated with tumor growth and spread. Studies have shown a correlation between a high concentration of VEGF and ascites development (excess fluid in the body cavity), disease worsening, and a poorer prognosis in women with ovarian cancer.
Biological effects of VEGF
Bevacizumab is an antibody that specifically binds and blocks the biological effects of VEGF, which is the key driver of tumor angiogenesis, a fundamental process required for a tumor to grow and to spread (metastasize) to other parts of the body. The precise mode of action of bevacizumab allows it to be combined effectively with a broad range of chemotherapies and other anti-cancer treatments. Bevacizumab helps to control tumor growth and extend survival with only a limited impact on the side effects of chemotherapy.
?We are very pleased with the results of the OCEANS study, as women with ovarian cancer need new treatment options,? said Hal Barron M.D., Chief Medical Officer and Head Global Product Development. ?Avastin has now demonstrated a significant improvement in PFS in ovarian cancer in three large phase III studies and we are looking forward to sharing the data at an upcoming medical meeting.?
The results from this trial build on findings from two previous phase III studies (GOG 0218 and ICON7) in women with newly diagnosed ovarian cancer. Both of these studies demonstrated that front-line bevacizumab in combination with standard chemotherapy (carboplatin and paclitaxel), followed by the continued use of bevacizumab alone, significantly increased the time women with ovarian cancer lived without their disease getting worse, compared to those treated with chemotherapy alone. Roche has submitted a European Union (EU) marketing authorization application for the use of bevacizumab in the front-line setting, based on the results from GOG 0218 and ICON7 and expects a decision from the Committee for Medicinal Products for Human Use (CHMP) later this year. Genentech plans to submit applications in the US for the use of bevacizumab in ovarian cancer in 2011.
The GOG 0218 Study
Results from the GOG 0218 study  in 1,873 women with previously untreated advanced epithelial ovarian, primary peritoneal or fallopian tube carcinoma, who had already had surgery showed that women who received bevacizumab (15mg/kg) in combination with chemotherapy (paclitaxel and carboplatin), and continued use of bevacizumab alone for a total duration of 15 months, had a median PFS of 14.1 months compared to 10.3 months in women who received chemotherapy alone (hazard ratio = 0.72, p<0.0001). This is a 39% improvement in the likelihood of living longer without the disease worsening, which corresponds to a 28% reduction in the risk of cancer progression or death.
The GOG 0218 study protocol allowed for different ways to determine if a patient?s disease had progressed. Disease progression was measured using both levels of a protein (CA-125) and a radiograph/scan. (CA-125 is measured by a blood test and is sometimes used to demonstrate a response to chemotherapy or to diagnose a recurrence or progression of ovarian cancer.)
An analysis of efficacy was conducted for regulatory purposes that only included disease progressions determined by radiographs/scans (excluding progressions based on CA-125 alone). In this analysis, women who continued bevacizumab, following bevacizumab in combination with chemotherapy, had a median PFS of 18.2 months compared to 12.0 months in women who received chemotherapy alone, increasing the likelihood of them living longer without the disease worsening by 56% (based on a hazard ratio = 0.64, p<0.0001, which corresponds to a 36% reduction in the risk of cancer progression or death). Adverse events were consistent with those observed in pivotal trials of bevacizumab.
The ICON7 Study
In a second phase III international study  in 1,528 women with previously untreated epithelial ovarian, primary peritoneal or fallopian tube carcinoma, women who received bevacizumab (7.5mg/kg) in combination with chemotherapy (paclitaxel and carboplatin), and continued use of bevacizumab alone for a total duration of up to 12 months, had a median PFS of 18.3 months compared to 16 months in women who received chemotherapy alone (hazard ratio = 0.79, p = 0.0010). This is a 27% improvement in the likelihood of living longer without the disease worsening, which corresponds to a 21 percent reduction in the risk of cancer progression or death, Adverse events were consistent with those observed in pivotal trials of bevacizumab.
 Garcia M et al. Cancer Facts & Figures 2007. Atlanta, American Cancer Society, 2007
 Burger RA, et al. Phase III trial of bevacizumab (BEV) in the primary treatment of advanced epithelial ovarian cancer (EOC), primary peritoneal (PPC) or Fallopian tube cancer (FTC): A Gynaecologic Oncology Group study. J Clin Oncol 2010; 28 (June 20 Suppl.): 946s (Abstract LBA1)
 Perren T, et al. ICON7: A phase III Gynaecologic Cancer InterGroup (GCIG) trial of adding bevacizumab to standard chemotherapy in women with new
ly diagnosed epithelial ovarian (EOC), primary peritoneal (PPC) or Fallopian tube cancer (FTC). Oral presentation at ESMO 2010 (Abstract LBA4)
For more Information:
A Study of Carboplatin and Gemcitabine Plus Bevacizumab in Patients With Ovary, Peritoneal, or Fallopian Tube Carcinoma (OCEANS).