Olaparib, a drug treatment currently listed on the PBS for advanced ovarian cancer, is being trialed as a potential treatment for triple negative breast cancer.

Olaparib to be tested on Australian breast cancer patients for the first time

 

  • The OlympiA Study will investigate whether olaparib, a drug treatment for ovarian cancer, is effective for treating breast cancer
  • The trial will enrol 1,500 patients in approximately 500 centres worldwide including Australia
  • Participants include women and men diagnosed with triple negative breast cancer with an inherited BRCA1 or BRCA2 gene mutation

Earlier this year, it was announced that olaparib, a drug treatment for advanced ovarian cancer, had been added to the Pharmaceutical Benefits Scheme (PBS).

Jane Hill, CEO of Ovarian Cancer Australia heralded the listing as the most significant development in 30 years for treating advanced ovarian cancer among women who have a BRCA1 or BRCA2 gene mutation:

“Although olaparib is not a cure for ovarian cancer, it is a significant development as it reduces disease progression by 70% while preserving a good quality of life for women with advanced ovarian cancer.”

Australia and New Zealand Breast Cancer Trials Group are now undertaking a clinical trial to investigate whether olaparib is an effective treatment for patients with high risk negative primary breast cancer. The OlympiA study will enrol 1,500 patients in approximately 500 centres worldwide, including 15 hospitals across Australia.

The trial is open to both women and men diagnosed with triple negative breast cancer, provided they have an inherited BRCA1 or BRCA2 gene mutation. Triple negative breast cancer refers to breast cancer that lacks receptors for the hormones progesterone and oestrogen, or for the protein HER2.[1]

Pathology tests play a key role in the OlympiA trial. Before treatment begins, patients must undergo blood tests and urine tests to assess their overall health. The trial team will also analyse at least one sample of cancer cells that were removed during surgery or biopsy. If breast cancer returns during the trial, the patient will be asked to do another biopsy to assess the severity of the relapse.

Patients will have a number of blood tests in the first few months of treatment to monitor their response to the treatment. Blood tests may need to continue for 10 years to keep track of their progress. Results of the study will be released after March 2018 when the trial is complete.

Approximately 80% of all breast cancers are HER2 negative, and about 5% of these breast cancers also have an inherited BRCA1 or BRCA2 gene mutation.[2]

The OlympiA clinical study is investigating whether taking olaparib tablets twice a day for 12 months can reduce the risk of breast cancer coming back after finishing standard treatment. Participants will have a 50:50 chance of receiving either olaparib or a placebo (inactive “sugar tablet”).

Similar trials have already shown positive results. In the US, the OlympiAD trial was conducted to assess the efficacy and safety of olaparib compared with chemotherapy in patients with BRCA-mutated metastatic breast cancer. The results so far have shown that olaparib reduces the risk of cancer growth by as much as 42 percent compared to standard chemotherapy treatment.[3] For patients in the olaparib group, the response rate was more than double that of patients treated with chemotherapy.

It is still early days for the OlympiA study but if results are positive, this could be a crucial step toward building a case for making olaparib available to breast cancer patients in Australia.

[1] A trial to see if olaparib can reduce the risk of breast cancer coming back after treatment (OLYMPIA) – Cancer Research UK

[2]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3870050/

[3] Lynparza significantly reduces the risk of disease worsening or death in patients with BRCA-mutated metastatic breast cancer – AstraZeneca