Weekly chemotherapy with bevacizumab improves ovarian cancer survival compared to having it once every three weeks
20 Oct 2025
Results from the ICON8B trial showed that, for women with high-risk advanced ovarian cancer, combined chemotherapy and bevacizumab treatment improves survival when one chemotherapy drug, paclitaxel, is given weekly rather than every three weeks. These results were presented yesterday at ESMO in Berlin, Germany.
Ovarian cancer is the sixth most common cancer in UK women. The standard treatment usually involves surgery and chemotherapy, either before or after surgery. Standard chemotherapy uses two drugs, carboplatin and paclitaxel, which are given every three weeks over about four months. Some patients also receive bevacizumab, a drug that helps block the cancer’s blood supply and slow its growth. It’s given alongside chemotherapy and then continued for up to a year for high-risk cases.
The ICON8B trial explored two ways of giving chemotherapy and bevacizumab to treat advanced ovarian cancer. Women with high-risk stage III or IV ovarian, fallopian tube, or peritoneal cancer were eligible to take part in the trial.
579 women took part in ICON8B, and they were allocated at random to a treatment group:
- Standard chemotherapy and bevacizumab. Carboplatin and paclitaxel were given every three weeks for up to 18 weeks, alongside bevacizumab (chemotherapy phase). Bevacizumab then continued to be given every 3 weeks for up to 42 weeks (maintenance phase).
- Weekly chemotherapy and bevacizumab. Paclitaxel was given once a week at a lower dose, while carboplatin and bevacizumab were given every 3 weeks for up to 18 weeks (chemotherapy phase). Bevacizumab then continued to be given every 3 weeks for up to 42 weeks (maintenance phase).
In both groups, patients could have surgery either before starting chemotherapy or after they had received three cycles of chemotherapy.
After following up the participants for an average of six years, the results showed that women having weekly chemotherapy with bevacizumab live about 10 months longer than those receiving the standard chemotherapy with bevacizumab.
These findings align with the initial results of ICON8B presented in 2023, which showed that weekly chemotherapy combined with bevacizumab was more effective at preventing ovarian cancer coming back than the standard chemotherapy, after following up participants for an average of five years.
These results show that weekly chemotherapy in combination with bevacizumab benefits women with ovarian cancer and should be considered a standard of care option for patients with high-risk, advanced ovarian cancer.
As part of ICON8B, researchers also carried out quality-of-life studies and presented these findings at the ESMO Conference. They found that weekly chemotherapy and chemotherapy given every three weeks both had a similar impact on women’s global quality of life. However, women receiving weekly chemotherapy had longer-lasting neuropathy, which causesnumbness and tingling, than those receiving chemotherapy every three weeks. This is a common side effect of the drug paclitaxel. The ICON8B team is also planning to carry out economic analysis to assess the cost-effectiveness of giving more frequent chemotherapy with bevacizumab.
The ICON8B was designed and run by the MRC Clinical Trials Unit at UCL. The trial was led by Dr Andrew Clamp, a consultant medical oncologist based at The Christie NHS Foundation Trust, and funded by Cancer Research UK.
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