Bevacizumab Plus Chemotherapy May Improve Overall Survival In High-Risk Ovarian Cancer

Gunnar Kristensen, MD, PhD

Concurrent and continued bevacizumab added to standard chemotherapy with carboplatin/ paclitaxel improved overall survival (OS) in women with high-risk ovarian cancer, according to an interim survival analysis of the ICON7 trial. A trend toward improved OS was observed in the overall study population, which included women with newly diagnosed high-risk or advanced epithelial ovarian, primary peritoneal, or fallopian tube cancer. At last year’s ASCO meeting, first results of ICON7 showed a progression-free survival (PFS) benefit of about 1.5 months for the addition of bevacizumab compared with standard therapy.

“It’s too early to reach firm conclusions about the full extent of the overall survival benefit of adding bevacizumab to the treatment regimen for newly diagnosed ovarian cancer, but it does seem very promising, particularly for patients at high risk of recurrence,” said Gunnar Kristensen, MD, PhD, senior consultant in the Department of Gynecologic Oncology at Norwegian Radium Hospital in Oslo, Norway. “We don’t have all the answers today. We will have to wait for final results of the trial, which are expected in about 2 years.” Based on the trial results thus far, Kristensen said that in his practice he restricts bevacizumab to the high-risk group.

The study randomized 1528 women to receive 6 cycles of carboplatin/paclitaxel either with or without bevacizumab; in the bevacizumab arm, the drug was continued for a total duration of 12 months.

Two regulatory agencies—the FDA in the United States and the European Medicines Agency— requested an interim analysis of survival for consideration of a licensing application, and these were the results Kristensen presented at ASCO.

At a median follow-up of 28 months, fewer deaths were reported in the bevacizumab arm compared with standard therapy: 178 versus 200, respectively, with a hazard ratio of 0.85 (95% CI, 0.69-1.04), showing a trend toward improved survival. However, in a subset of women with high-risk ovarian cancer (stage III, suboptimally debulked with >1 cm of tumor left and stage IV), the addition of bevacizumab achieved a 36% reduction in risk of dying: 33% of the bevacizumab group were dead versus 47% of those treated with standard chemotherapy.

“This represents a median gain in survival of about 8 months,” said Kristensen.

ICON7 employed a 7.5 mg dose of bevacizumab; other trials have used 15 mg. The optimal dose and duration of treatment are not clear.

“These data support a potential role for bevacizumab as the first biologic agent for the treatment of ovarian cancer,” said Andrew Seidman, MD, of Memorial Sloan-Kettering Cancer Center in New York. Seidman moderated a press conference where these data were presented.

Kristensen G, Perren T, Qian W, et al. Result of interim analysis of overall survival in the GCIG ICON7 phase III randomized trial of bevacizumab in women with newly diagnosed ovarian cancer. J Clin Oncol. 2011;29(suppl; abstr LBA5006).