Stockholm, Sweden: Until recently, options for patients with bone metastases from advanced prostate cancer have been very limited. But now the first Phase III study of an alpha-pharmaceutical in these patients has shown that it can prolong survival significantly, according to research reported today (Saturday) at the 2011 European Multidisciplinary Cancer Congress .
Dr. Chris Parker, Consultant Clinical Oncologist at the Royal Marsden Hospital, London, UK, told the congress that the ALSYMPCA international Phase III study of the drug Radium-223 Chloride (Alpharadin TM) in 922 prostate cancer patients who were resistant to hormone treatment and had bone metastases, had been stopped early once an interim analysis by the Independent Data Monitoring Committee (IDMC) in June 2011 had revealed that patients receiving the best standard treatment plus radium-223 were living longer than those who were receiving the same standard treatment plus placebo. The hazard ratio was 0.695, (p = 0.00185), meaning that patients taking radium-223 had a 30% lower rate of death compared to patients taking placebo. Median overall survival for patients taking radium-223 was found to be 14 months, compared with 11.2 months in the placebo group. "It would have been unethical not to offer the active treatment to those taking placebo," Dr. Parker said.
Alpha-pharmaceuticals work by delivering minute, highly charged and targeted doses of damaging radiation to a secondary tumour (metastasis) in the bone. Radium is similar to calcium in that it sticks to bone, and particularly to where new bone is being formed, so it is a highly effective way of delivering radiation to a target. "It takes only a single alpha particle to kill a cell," Dr. Parker explained, "and collateral damage is minimised because the particles have such a tiny range a few millionths of a metre (micrometres). So we can be sure that the damage is being done where it should be, to the metastasis, and ver
|Contact: Mary Rice|
ECCO-the European CanCer Organisation