Preliminary data were reported this week on the use of a new type of anticancer drug. Combretastatin A4 is called a vascular targeting agent and is designed to cut off the blood supply to a tumour. In a phase 1 study under way at Mount Vernon hospital and the Hammersmith hospital, nuclear magnetic resonance imaging has shown reduced blood flow to tumours after treatment with the drug.
Dr Gordon Rustin (director of the department of medical oncology, Mount Vernon hospital) said: "It is the first time in cancer research that a drug has been shown to reduce blood flow to patients' tumours. This proves that the theory of starving someone's tumour of oxygen can work in practice and it has opened the door for new cancer treatments in the future." Combretastatin A4 is being developed by the Cancer Research Campaign and biotechnology company Oxigene. The CRC says that the drug is thought to have a greater effect on endothelial cells that are proliferating (as in tumour vessels) than those that are quiescent (as in normal vessels) but further work is needed to assess its selectivity.
Combretastatin A4 differs from the anti-angiogenesis drugs, such as angiostatin, that are being developed. These are intended to inhibit the establishment of a tumour blood supply, as opposed to attacking established vasculature.