Ovarian cancer pill can help men

A precision drug, created to treat tumors with specific genetic mutations and used to treat women with inherited cancers, was shown to benefit men with untreatable prostate cancer, according to a recent clinical trial.

Now olaparib is not approved for use on the NHS by the National Institute for Health and Care Excellence (Nice) or the Cancer Drugs Fund. Nice is still in the process of considering whether to recommend the drug for women with ovarian cancer. In this trial, those men will be enrolled who have prostate cancer having similar detectable gene defects. The clinical trials discovered that around 30 percent of men who were suffering from advanced prostate cancer had tumors with various defects in their system and these defects responded very well to the drug olaparib.

Levels of Prostate Specific Antigen, which is produced by tumours, was more than halved and there were also significant falls in the number of prostate cancer cells detected in the blood and in the size of secondary tumours.

“We showed that a subset of men whose tumours had mutations in their DNA fix machinery responded particularly well to treatment with olaparib”.

Known as olaparib, the drug was originally licensed and marketed for women with ovarian cancer – but a new trial by the Institute of Cancer Research found that it could also slow tumour growth in men with prostate cancer.

The research team, based at the Institute of Cancer Research in London (ICR) and The Royal Marsden NHS Foundation Trust, checked genetic data for these 16 patients and found that each carried faults in genes linked with DNA fix, potentially explaining their response to the drug.

In this trial of PARP inhibition in prostate cancer (TOPARP-A), investigators treated all patients with olaparib while also obtaining fresh tumor-biopsy samples in order to conduct biomarker studies from both germline and somatic DNA. 16 responded to the treatment, or 33%. Further analysis showed that the tumours of those who did respond had developed faults in genes linked with a cell’s ability to fix its DNA. This type of drug blocks enzymes that are involved with DNA fix, which is a characteristic of cancer, of course. “Therefore, we believe we have found a way to predict which patients are likely to respond to this new therapy”.

“In other words, these findings may apply to as many as one-third of castrate-resistant prostate cancer patients with metastases, which is huge”, Sartor said. “I am encouraged by the response rate”, he said.

The study also received funding from the Prostate Cancer Foundation, Stand Up To Cancer, Prostate Cancer United Kingdom and the Movember Foundation.