Gene-Targeted Rx Offers Hope for Prostate Cancer

Olaparib may benefit prostate cancer patients, including those without inherited cancers

/ Author:  / Reviewed by: Anyssa Garza, PharmD

(RxWiki News) Prostate cancer can be tough to treat once it has spread throughout the body. But a new, gene-targeting pill may soon be here to help.

A new study from the UK found that the experimental drug olaparib, which was first developed to treat women with inherited cancers, may also benefit men with advanced prostate cancer.

According to the authors of this study, this trial is a milestone in cancer treatment. It's the first to demonstrate the benefits of treatment matched to the particular genetic characteristics of a patient's cancer.

"Our trial marks a significant step forward in the treatment of prostate cancer, showing that olaparib is highly effective at treating men with DNA repair defects in their tumors," said Johann de Bono, MD, the head of drug development at the Institute of Cancer Research and the Royal Marsden NHS Foundation Trust, in a press release. "I hope it won't be long before we are using olaparib in the clinic to treat prostate cancer, or before genomic stratification of cancers becomes a standard in this and other cancers."

Prostate cancer occurs in a man's prostate (a gland that produces seminal fluid). According to the National Cancer Institute, about 14 percent of men will be diagnosed with prostate cancer at some point during their lifetime.

For this study, Dr. de Bono and team looked at 49 men with treatment-resistant, advanced prostate cancer. All of these men were treated with olaparib at a dose of 400 milligrams twice a day. Of these patients, 16 (33 percent) responded to treatment.

Of these 16 patients who responded to treatment, 14 (88 percent) responded well. Olaparib was found to generate falls in prostate-specific antigen levels and circulate tumor cell counts in the blood.

The patients who didn't inherit cancer genes, but whose tumors had mutations in DNA repair, responded particularly well to olaparib.

According to Dr. De Bono and team, these results have led to a second trial, in which only prostate cancer patients who have detectable DNA repair mutations will receive olaparib.

If the results are successful, olaparib could become a standard treatment option for men with advanced prostate cancer and DNA repair mutations, according to these researchers.

"This trial is exciting because it could offer a new way to treat prostate cancer by targeting genetic mistakes in cancers that have spread," said Aine McCarthy, science information officer at Cancer Research UK, in a press release. "The hope is that this approach could help save many more lives in the future."

Olaparib, which is now owned by AstraZeneca, was licensed last year for the treatment of women with ovarian cancer and inherited BRCA gene mutations. The drug has not yet been approved for prostate cancer patients.

This study was published online Oct. 28 in the New England Journal of Medicine.

Cancer Research UK and the National Institute for Health Research, among others, funded this research.

Several study authors disclosed potential conflicts of interest, such as ties to companies that make drugs used in cancer treatment.

Reviewed by: 
Review Date: 
October 28, 2015
Last Updated:
November 2, 2015