Compared with those on chemotherapy alone, patients taking Avastin typically lived nearly four months longer.
The percentage of patients responding to therapy also increased by a third from 36% to almost half with the addition of Avastin.
The targeted drug, generically known as bevacizumab, is a laboratory-made antibody that directly combats the generation of tumour-nourishing blood vessels.
It is already approved in the European Union for advanced stages of bowel, ovarian, breast, lung and kidney cancers.
The latest results from the Phase III GOG240 trial, funded by the US National Cancer Institute, are published in the New England Journal of Medicine.
A total of 452 women with advanced cervical cancer that was not responding to standard treatment took part in the study in the US and Spain. Women given chemotherapy alone typically lived 13.3 months while those on Avastin survived for 17 months.