Immunotherapy has become a buzzword in oncology in recent years, thanks to its success in treating certain cancer types. It is not yet in routine use in the clinic as a treatment option for breast cancer in Australia, but breast cancer researchers are learning from the experiences of researchers in other cancer types, that previously had limited treatment options.

Breast Cancer Trials Medical Advisor Dr Nick Zdenkowski says immunotherapy uses the patient’s own immune system to aid in their cancer treatment.

“The immune system’s job is to work out what’s foreign in the body. So, if you take an immune cell and show it that cancer cells are foreign, it can work on attacking and killing off those cells that express foreign proteins.”

A new immunotherapy clinical trial being coordinated by Breast Cancer Trials, called DIAmOND, aims to improve outcomes for patients with metastatic breast cancer by researching the effectiveness, safety and side effects of a new drug combination.

Despite recent advances, there are major limitations to current treatments, with most cancers developing resistance to HER2-targeted therapy and some types of HER2-positive breast cancer not responding to conventional chemotherapy. This trial is examining whether the combination of trastuzumab (anti-HER2 therapy) with durvalumab (PD-L1 inhibitor) and tremelimumab (CTLA4 inhibitor), will activate anti-tumour immune responses and improve clinical outcomes in patients with trastuzumab-resistant, metastatic HER2-positive breast cancer.

“The trial is currently enrolling patients with metastatic HER2-positive breast cancer, aiming to shrink and control all sites of cancer for as long as possible, with the hope that some of those patients will achieve a very durable response, similar to that seen in patients with melanoma and lung cancer,” said Dr Zdenkowski.

For more information about the DIAmOND clinical trial, visit www.breastcancertrials.org.au.