Abiraterone Before Hormone Therapy Improved Prostate Cancer Survival by Nearly 40%

The standard of care for men with prostate cancer could change for the better once again, new findings suggest.

In a study published in the New England Journal of Medicine, investigators found that adding abiraterone to hormone therapy at the start of prostate cancer treatment improves survival by 37%.

In a portion of the STAMPEDE trial, investigators recruited 1900 men with prostate cancer and divided them into 2 groups. Half of the men were treated with hormone therapy, while the remaining participants received hormone therapy and abiraterone.

The results of the study, presented at the 2017 ASCO annual meeting in Chicago, found that men in the abiraterone arm experienced a 70% reduction in disease progression.

“These are the most powerful results I’ve seen from a prostate cancer trial—–it’s a once in a career feeling,” said chief study investigator Professor Nicholas James. “This is one of the biggest reductions in death I’ve seen in any clinical trial for adult cancers.”

Typically, abiraterone is only administered to men with metastatic advanced prostate cancer who have stopped responding to standard hormone therapy. However, the new study indicates that abiraterone produces an added benefit when given prior to the start of long-term hormone therapy.

“Abiraterone is already used to treat some men whose disease has spread but our results show many more could benefit,” James said. “In addition to the improvements in survival and time without relapse, the drug reduced the rates of severe bone complications, a major problem in prostate cancer, by more than half. I really hope these results can change clinical practice.”

An estimated 46,500 men are diagnosed with prostate cancer each year in the UK, of whom, approximately 11,000 die from the disease.

“These results could transform the treatment of prostate cancer,” said Sir Harpal Kumar, chief executive at Cancer Research UK.

Prior data from the STAMPEDE trial already changed clinical practice, according to the study. Last year’s results led to docetaxel chemotherapy becoming part of the standard of care for many men with prostate cancer.

“The STAMPEDE trial is changing the face of prostate cancer because the flexibility of the trial design means that we can investigate a number of different treatment options rapidly and in parallel, enabling scientists to get results much more quickly than they usually would,” Kumar said. “Cancer Research UK scientists first discovered abiraterone and subsequently played a key role in its development, including funding the first clinical trials. This study adds to the importance of the drug.”