Prostate cancer gets first gene-targeted medicines

Image: Olaparib in AstraZeneca pill bottle.

The Institute of Cancer Research, London, has strongly welcomed the approval by the US Food and Drug Administration (FDA) of the genetically targeted drug olaparib for some men with advanced prostate cancer.

Men whose tumours have faulty DNA repair genes and who have not responded to prior treatment with the hormone therapies enzalutamide or abiraterone will now be able to benefit from olaparib – a pill lacking the side effects of chemotherapy.

Olaparib is a precision medicine that works by selectively targeting and killing cancer cells with faulty DNA repair machinery. The drug – part of a family of medicines called PARP inhibitors – has already been approved in the US and Europe for the treatment of ovarian and breast cancers and has also been approved in the US for the treatment of pancreatic cancer.

The decision by the FDA follows three days after it approved another PARP inhibitor, called rucaparib, for prostate cancer. Together, the medicines now become the first genetically targeted drugs for prostate cancer.

Approval based on PROfound trial

Scientists at The Institute of Cancer Research (ICR) discovered how to genetically target olaparib – which became the world’s first cancer drug targeted against inherited genetic faults when it was approved for the treatment of BRCA1 or BRCA2 mutant ovarian cancer back in 2014.

The approval of olaparib in prostate cancer is based on groundbreaking findings from the PROfound trial, which were published last month and demonstrated the drug's ability to block prostate cancer growth more effectively than the modern hormone treatments abiraterone and enzalutamide in men with faulty DNA repair genes.

The PROfound trial, co-led by Professor Johann de Bono at the ICR and The Royal Marsden NHS Foundation Trust, looked at men with prostate cancer who had one of 15 faults in genes involved in a cell’s ability to repair its DNA. It is particularly encouraging that olaparib has now been approved for its use in men with any of multiple DNA repair faults, not just BRCA defects.

This is the first time that a drug has been approved for cancers with faulty DNA repair genes beyond BRCA defects – such as ATM or PALB2 mutations.

Olaparib can now be used in the US to treat prostate cancer patients whether their DNA repair gene defects have been inherited or acquired during the development of a cancer.

'First ever precision medicines for prostate cancer'

Professor Johann de Bono, Professor of Experimental Cancer Medicine at The Institute of Cancer Research, London, and Consultant Medical Oncologist at The Royal Marsden NHS Foundation Trust, said:

“Olaparib has now become one of the first precision medicines for prostate cancer. It is the perfect example of how understanding the genetics of a patient and their cancer can be used to target the disease’s Achilles heel and personalise treatment. It is tremendously exciting to see this drug being approved in the US for this group of patients living with advanced prostate cancer.

“I’m looking forward to further reviews from the EMA and NICE over the coming months regarding its licensing and evaluation, with the hope of seeing olaparib become available on the NHS for these men in the next few years.”

Professor Paul Workman, Chief Executive of the ICR, said:

“It’s fantastic to see targeted treatment of prostate cancer take such great strides, first with the ICR-discovered drug abiraterone, and now with the gene-targeted medicine, olaparib.

“We’re incredibly proud at the ICR of our discovery of how to genetically target cancer with olaparib, and we’re delighted to see it now become licensed for prostate cancer in the US. I’m very hopeful that this will soon be followed by its authorisation in Europe, followed its approval by NICE for use on the NHS.”