Key Facts:
- The OPTIMA Pre-menopausal Extension study, building on the original OPTIMA trial, is opening in Australia and New Zealand to investigate whether younger women with breast cancer can safely avoid chemotherapy based on their genomic test results.
- The trial will enrol pre-menopausal women aged 35 to 54, using the Prosigna genomic test to measure gene activity and assign a risk score.
- Chemotherapy is routinely offered for early-stage breast cancer that has spread to nearby lymph nodes, but there is concern that many patients with hormone-receptor positive breast cancer gain little benefit whilst suffering significant side effects.
- The original OPTIMA trial demonstrated that patients with a low genomic risk score could achieve the same or better outcomes without increasing the risk of recurrence.
- Breast Cancer Trials’ CEO Karen Price highlighted the importance of the research during Breast Cancer Awareness Month, encouraging women diagnosed with breast cancer to speak with their medical team about potential eligibility for clinical trials.
A landmark clinical trial, which used a genomic test to demonstrate that many people aged 40 and over who are diagnosed with breast cancer can safely avoid chemotherapy, will be extended to address this very question specifically in pre-menopausal women.
Opening this month at sites in Australia and New Zealand, the OPTIMA Pre-menopausal Extension study builds upon the results of the OPTIMA (Optimal Personalised Treatment of early breast cancer using Multi-parameter Analysis) trial, run by Breast Cancer Trials in Australia and New Zealand.
OPTIMA recruited women and men aged 40 or older following surgery for newly diagnosed hormone-receptor positive breast cancer, with the findings indicating that people whose tumours had a low genomic test score could be treated safely with hormone blocking therapy alone and still achieve the same or better outcomes, sparing them the side effects of chemotherapy without increasing the risk of the cancer returning.
The new study will lower the minimum age of trial participants and enrol premenopausal women aged 35 to 54 years), and use the same genomic test called Prosigna, which measures the activity of genes involved in breast cancer growth and provides a genomic risk score.
Chemotherapy is generally offered to people with early‑stage breast cancer that has spread from the breast to nearby lymph nodes, as it lowers the risk of the disease returning on average. While effective overall, there is concern that many people with hormone‑receptor positive breast cancer, the most common type of breast cancer, receive little or no benefit from chemotherapy but still experience significant side effects. This is particularly relevant in premenopausal women, because chemotherapy in young women can cause permanent ovarian failure and infertility.
This new trial aims to find out if chemotherapy can be avoided in younger women where the Prosigna test shows a low genomic risk score and modern hormone-blocking therapies are used.
Breast Cancer Trials’ Study Chair, A/Prof Belinda Kiely, explains, “Traditionally we’ve given chemotherapy and hormone-blocking therapy to all patients with a high risk cancer, but we recognise that many people receive chemotherapy unnecessarily, and the problem with chemotherapy is that it has a lot of side effects, particularly in younger women.
“In the future, I would like to see all women with hormone receptor positive breast cancer being offered one of these tests when they’re diagnosed, so they can get that information early on to help with their decision-making and planning.”
Samantha Phillips was diagnosed with ER+/PR+ HER2- breast carcinoma in 2024, at the age of 46, after her partner noticed an indentation in her breast. Balancing a busy career as a CEO and a hectic family life, she joined the OPTIMA trial and was randomised to the treatment arm that avoided chemotherapy. Samantha had two surgeries, radiotherapy and continues on hormone-blocking therapy.
“There are times that I wonder if the treatment isn’t worse than the cancer itself,” she says. “Being able to be clearer on the benefits of the treatment is critical. Putting women through treatment that seriously impacts both short term and long term quality of life without knowing that it really helps is, in my opinion, too much to ask and doesn’t result in an informed decision. For me, knowing the results of the genomic test through the OPTIMA trial meant I was able to get on with life as I knew it – without having to quit my job or pause my career.”
Breast Cancer Trials CEO Karen Price said it was fitting that this important research should be highlighted during Breast Cancer Awareness Month.
“For many younger women diagnosed with breast cancer, treatment decisions can have lifelong consequences – including impacts on fertility and quality of life,” explains Ms Price. “This study reflects exactly why clinical trials are so important: they help us ask whether we can treat people more precisely, avoid unnecessary side effects, and still protect survival outcomes. During Breast Cancer Awareness Month, we encourage women diagnosed with breast cancer to speak with their medical team about whether a clinical trial may be right for them.”
About us:
Founded in 1978, Breast Cancer Trials conducts a multicentre national and international clinical trials research program into the treatment and prevention of breast cancer. Every breast cancer treatment available today has been proven through clinical trials research. The work of Breast Cancer Trials has improved the treatment of breast cancer, led to changes in the way breast cancer is managed and has saved thousands of lives. More than 1,000 researchers in 118 institutions across Australia and New Zealand are committed to the vision of no more lives cut short.
