Researchers to examine whether incurable cancer can be treated with existing drug

Researchers will now test in the lab if Talazoparib is effective in treating secondary breast cancer in the brain.

Irish researchers are to examine whether an incurable type of cancer can be treated using an existing drug.

A new study, funded by UK charity Breast Cancer Now, will explore if the drug talazoparib (Talzenna) could be used to treat people with incurable secondary metastatic breast cancer which has spread to the brain.

The drug is currently used to treat other breast cancers by preventing cancer cells with altered BRCA genes from repairing their DNA, and forcing them to die.

Secondary breast cancer occurs when breast cancer cells spread from a primary tumour in the breast, through the lymphatic or blood system to other parts of the body where it becomes incurable.

There are limited treatment options available for these patients, and a lot of drugs are unable to reach these tumours because of the brain’s natural protection.

A team, led by Professor Leonie Young and Dr Damir Vareslija from RCSI University of Medicine and Health Sciences, will investigate if Talazoparib could be used to treat secondary breast cancer in the brain.

Through previous research, which analysed tumour samples donated by people whose breast cancer has spread to the brain, the team established that almost half of the tumours had changes in the way they repair their DNA, which could make these tumours vulnerable to PARP inhibitors like Talazoparib.

Using tumours and breast cancer cells donated by patients, researchers will now test in the lab if Talazoparib is effective in treating secondary breast cancer in the brain.

The researchers aim to identify key features of a tumour that responds to this type of treatment to establish who could benefit most.

Professor Young said their previous research leads the team to be hopeful that secondary breast cancer tumours in the brain could be vulnerable to drugs like Talazoparib.

“People are always at the heart of the research we do and we are always trying to answer questions that are important to our patients,” she said.

“The support of Breast Cancer Now will enable us to learn more about the effectiveness of these powerful drugs to hopefully treat people with secondary breast cancer which has spread to the brain in the future.” 

Dr Simon Vincent, director of research, of Breast Cancer Now, said they hope the research can "lead to effective new treatments".

 “We desperately need to discover new ways to treat this incurable disease, including for those whose breast cancer has spread to the brain and who have very limited treatment options.”