Game-changing drug could cure deadly ovarian cancer

Women with the most deadly type of ovarian cancer could now be eligible for this game-changing drug, which researchers believe could cure them.

Women with the most deadly type of ovarian cancer should now be eligible for game-changing drugs researchers believe could cure them, following a landmark finding by Melbourne scientists.

The work led by Walter and Eliza Hall Institute of Medical Research has uncovered that tumours in a group of ovarian cancer patients contain gene-silencing changes that make them responsive to powerful targeted drugs called PARP inhibitors.

Lead researcher Professor Clare Scott said the discovery identified an extra 12 per cent of women with high-grade serous ovarian carcinoma, who were likely to benefit from these drugs and should be included in clinical trials.

“We’ve proven that if you don’t give this treatment early – as soon as they’ve finished chemotherapy – then the gene silencing … this cotton wool just falls off like fairy floss over time, and later on the drug is not going to work,” Prof Scott said.

The findings come after Prof Scott’s laboratory’s uncovered three years ago how gene silencing worked in ovarian cancer, and exposed the potential benefits of getting more women with BRCA1 silencing on targeted treatment.

Researchers believe the drug could possibly be life saving.

This time they looked at another ovarian cancer susceptibility gene called RAD51C.

In laboratory work led by Dr Ksenija Nesic, they used patient samples to regrow more pure tumours in mice for analysis.

They treated these with two PARP inhibitors, uncovering that RAD51C silencing must be absolute for drugs to work.

“It also showed us that the best therapy for a patient could change over time,” Dr Nesic said. “In the future, women should have their tumours monitored and if their cancers lose their gene silencing, they should be offered alternative therapies.”

The findings were published on Thursday in the journal Cancer Research.

But subsidised access is the current hurdle.

Australian women with BRCA mutations – about 20 per cent of ovarian cancers – can access PARP inhibitors early in treatment.

Despite many other countries funding early access for women without BRCA mutations, Australia only funds it once a cancer has returned.

Prof Scott said given the success of these drugs in BRCA mutations, she now wanted this same life-extending, or possibly life-saving, potential given to this new subset of women.

“We’ve never been in a position to say the word cure in the press. I would never do that before. But now I will,” she said. “I am confident we are curing some women with a BRCA-1 or 2 mutation who receive a PARP inhibitor in the first line following their chemotherapy.

“Now we’re seeing if we can cure some women who don’t have a BRCA mutation.”