Alpha particles used to treat prostate cancer that has spread to bone

In collaboration with the Press Association

An experimental drug that delivers small doses of radiation to cancer that has spread to the bone has proved effective in treating patients with an advanced form of prostate cancer.

Radium-223 chloride (also called Alpharadin) has been found to prolong survival in men whose prostate cancer has spread to their bones.

Advanced prostate cancer spreads to the bones in around 90 per cent of patients, and once a cancer has spread it is more difficult to treat it successfully.

The alpha-pharmaceutical treatment delivers a small, highly charged and targeted dose of radiation to these secondary bone tumours.

A Phase III trial of the drug involving 922 patients was stopped early because of its high success rate.

Patients who were given the best standard treatment plus radium-223 were found to live longer than those who received the same standard of treatment plus a placebo drug.

Reporting the findings at the European Multidisciplinary Cancer Congress, researcher Dr Chris Parker said the average survival rate for patients taking radium-223 was 14 months, compared with 11.2 months in the other group.

Patients taking radium-223 had a 30 per cent lower rate of death compared with patients taking the placebo.

Dr Parker, a consultant clinical oncologist at the Royal Marsden Hospital in London, added: "I have no doubt that there will be further trials looking at a combination of radium-223 with other drugs that are currently used in prostate cancer, and that there will also be studies using radium earlier in the disease.

"Additionally, the drug could be used in many other types of cancers which metastasise to bone, regardless of the primary site."

Researchers say the drug has relatively few side effects, and they plan to submit their data for approval from drug regulators.

Prof Gillies McKenna, Cancer Research UK's radiotherapy expert and director of the Gray Institute for Radiation Oncology and Biology, said: "This appears to be an important study using a highly targeted form of radiation to treat prostate cancer that has spread to the bones.

"This research looks very promising and could be an important addition to approaches available to treat secondary tumours - and should be investigated further."

Copyright Press Association 2011