Adding the drug bevacizumab to chemotherapy for ovarian cancer can slow down the disease and may improve overall survival in women at high risk of recurrence, according to new research from an international research team led by the Medical Research Council, St James’s Institute of Oncology in Leeds, and the Princess Margaret Hospital, Toronto.
The interim results from a large-scale clinical trial known as ICON7, published in the New England Journal of Medicine, suggest that bevacizumab delays progression of the disease by an average of two months, compared with standard chemotherapy.
The effect appeared largest in women with the most aggressive disease. In these women the disease was stalled for almost six months. There was also a trend towards improved overall survival in these women. However, the researchers will not know for certain whether the drug extends the overall life expectancy of ovarian cancer patients until the final results are reported in 2013.
Chief investigator Dr Tim Perren, Consultant Oncologist from St James’s Institute of Oncology, St James’s University Hospital, Leeds and Honorary Senior Lecturer at the University of Leeds, said:
"These results are potentially very encouraging particularly for women with advanced ovarian cancer. Bevacizumab is the first new drug for 15 years to show an advantage over existing treatments for women with this disease. These results are however preliminary and will not be fully confirmed until early 2013."
Professor Max Parmar, Director of the MRC Clinical Trials Unit and co-author of the study, said:
"This suggests that bevacizumab could be considered as a treatment for women with an advanced form of the disease, or whose cancer has come back after chemotherapy treatment. However, the decision on whether to include the drug routinely should be delayed until we have further evidence on its impact on overall survival."
Ovarian cancer is the sixth most common cancer in women in the UK with 6,500 new cases diagnosed each year. As two-thirds of women are diagnosed at an advanced stage of the disease, survival rates are poor. There has been little improvement in overall survival rates since the introduction of the chemotherapy drug paclitaxel 15 years ago.
Bevacizumab is a ‘targeted’ cancer therapy that works by blocking the development of new blood vessels and interfering with the tumour’s ability to grow and spread to other parts of the body. Combining bevacizumab with chemotherapy has been shown to improve the effectiveness of treatment in several other forms of the disease including lung, breast and colorectal cancers. ICON7 aimed to find out if this was also the case in ovarian cancer.
The trial followed 1,528 ovarian cancer patients who were randomly allocated to receive either standard chemotherapy, or a combination of standard treatment and bevacizumab, following surgery to remove their tumour. The researchers recorded the time taken for the disease to return, measured by CT scan.
The interim results of ICON7 – reported after 28 months of follow-up – are supported by the findings of an American trial of bevacizumab (GOG218) which is published in the same issue of the New England Journal of Medicine as ICON7.
The ICON7 trial is sponsored by the Medical Research Council, run through the Gynecologic Cancer Intergroup - an international cooperative group for clinical trials in gynaecological cancers. Funding for running costs is provided by the pharmaceutical company Roche. This trial was supported in the UK by the National Institute for Health Research Cancer Research Network (NCRN).
For more information about this story, see this policy brief exploring what is known about bevacizumab for treating ovarian cancer.