A new drug to combat aggressive prostate cancer could be available within a year to patients who are no longer responding to current treatments.
The pill, abiraterone acetate, could be available sooner that anticipated as the Phase III trial – the final test stage before the drug goes to market – showed that patients taking the pill were doing far better than those given a placebo drug.
Applications will now be made to market the drug worldwide, but its availability in the UK will still depend on whether it is cost effective enough to be offered for free to NHS patients.
“This is extremely exciting” Dr Johan de Bono, study leader
Around 35,000 men are diagnosed with prostate cancer each year in the UK, and around 10,000 die from the disease.
Trial results
The final stage of the trial involved 1,195 patients from 13 countries who were aged between 40 and 75 years old. All the patients had advanced prostate cancer which had spread and was still progressing despite hormone and chemotherapy treatments.
The men were divided into two groups. Each was given a low does of steroid drugs plus either abiraterone or a placebo drug.
Those on the abiraterone lived longer – surviving an average of 14.8 months compared to those on the placebo who survived 10.9 months on average. Overall the risk of death also decreased by 35 per cent for those on the drug.
How abiraterone works:
Abiraterone acetate, owned by global pharmaceutical company Janssen, was developed by British scientists at the Institute of Cancer Research. The drug shuts off a tumour's ability to generate its own supply of testosterone.
The male hormone is known to fuel prostate cancer. While treatments already exist which block testosterone production in the body or stop it stimulating cancer, they cease to work when tumours start generating their own supply of the hormone.
Doctors then have to resort to chemotherapy drugs such as docetaxel, which tend to work for only short amounts of time.
Abiraterone targets an enzyme that plays a key role in the synthesis of testosterone. It is also taken as a pill, which makes treatment more convenient for patients.
Study leader Dr Johan de Bono, from the Institute of Cancer Research, said: “This is extremely exciting because men with this aggressive type of prostate cancer currently have very few treatment options and a poor prognosis.
“Around one man in the UK dies every hour from this disease, so the news that abiraterone acetate may extend survival with manageable side-effects will be incredibly important to men with prostate cancer and their families.”
The trial started in April 2009 and was not due to finish until June 2011, but it was “unblended” on ethical grounds last August when the results clearly showed that one group of patients were faring much better than the other.
Results from the trial were presented today at the European Society for Medical Oncology Congress in Milan, Italy.
‘Significant step forward’
Professor Malcolm Mason, from the charity Cancer Research UK, called the developments a “significant step forward”.
“These results showed that abiraterone provided a worthwhile extension to life in men who had exhausted all standard treatments for the disease and this makes this study particularly noteworthy.
“Researchers are planning trials to test abiraterone in men who have been diagnosed with prostate cancer at an earlier stage and there is hope that in several years clinical trials might show that the drug could effectively treat less advanced cases of the disease as well.”