Many women with breast cancer from the BRCA gene develop a form of breast cancer called triple negative breast cancer which can be very aggressive and hard to treat effectively.
The results from a new study released this week show that a new drug, belonging to the class of drugs called PARP Inhibitors, is producing exciting results in women with advanced BRCA-related breast cancer.
Findings from the phase III clinical trial of about 300 women found that compared to standard chemotherapy, the PARP inhibitor olaparib reduced the chance of progression of advanced, BRCA-related breast cancer by 42 per cent, delaying progression by about three months.
Dr Mark Robson from the Memorial Sloan Kettering Cancer Center in New York says, “It is especially encouraging to see that olaparib was effective against triple negative breast cancers that arise in women with inherited, germline BRCA mutations. This type of breast cancer is particularly difficult to treat and often affects younger women.”
How the treatment works
For those with a mutation or fault in their BRCA1 or BRCA2 gene, this fault lowers the cell’s ability to repair damaged DNA. Olaparib takes this idea and blocks other key players in the cell’s DNA repair machinery, called PARP1 and PARP2. Because of their underlying inability to repair DNA, cancer cells with BRCA mutations are particularly vulnerable to treatments that target PARP.
This drug is an example of the developing field of ‘personalised medicine’, which aims to match treatments to the specific genetic makeup of each tumour.
Director of Research Investment at the National Breast Cancer Foundation, Dr Alessandra Muntoni says, “The results of this study give hope to many women living with triple negative breast cancer that comes from an inherited BRCA mutation. These are exciting results that could help these women live longer in the future.”
Other exciting study results for new treatments
In a clinical trial for metastatic breast cancer, the drug abemaciclib was found to stop the cancer progressing for an extra seven months on average, compared with those on the drug fulvestrant alone.
This larger trial of 669 patients was for women with advanced HER2 negative, hormone receptor positive cancer that has become resistant to hormone therapy such as tamoxifen.
This type of cancer affects about 70 per cent of women with the disease and many eventually become resistant to hormone therapy.
The study showed that women taking a combination of abemaciclib and fulvestrant lived for 16.4 months on average, compared with 9.3 months for those on fulvestrant alone.
Abemaciclib is one of an exciting new class of drugs called CDK4/6 inhibitors that aim to stop cancer cells multiplying out of control by targeting two of the crucial proteins involved.