, pub-5475981771945671, DIRECT, f08c47fec0942fa0

Women With Node-positive, Early-stage Breast Cancer Can Avoid Chemotherapy

Women With Node-positive, Early-stage Breast Cancer Can Avoid Chemotherapy

MADISON, Wis., Dec. 3, 2021 /PRNewswire/ — Exact Sciences Corp. (NASDAQ: EXAS) today announced that data from the Rx for Positive Node, Endocrine Responsive Breast Cancer, or RxPONDER, trial were published in The New England Journal of Medicine.

The study, led by the independent SWOG Cancer Research Network and sponsored by the National Cancer Institute (NCI), successfully defined the benefit of chemotherapy in early-stage, node-positive breast cancer patients with Oncotype DX Breast Recurrence Score results of 0 to 25. Initial results from RxPONDER were reported at the 2020 San Antonio Breast Cancer Symposium (SABCS). The findings have now been confirmed in this peer-reviewed publication.

In the study, postmenopausal women with 1 to 3 positive nodes and Recurrence Score® results of 0 to 25 showed no benefit from chemotherapy after a median of five years of follow-up, meaning they can potentially avoid negative side effects of the treatment. Importantly, no chemotherapy benefit was observed regardless of the number of affected nodes, tumor grade or size. In premenopausal women with 1 to 3 positive nodes, a statistically significant chemotherapy benefit was observed.

Approximately one-third of patients diagnosed with hormone receptor (HR)-positive, HER2-negative early breast cancer have a tumor that has spread to their lymph nodes. The vast majority of these patients currently receive chemotherapyii even though approximately 85% of them have Recurrence Score results of 0 to 25.iii In addition, approximately two out of three early-stage breast cancer patients are postmenopausal.iv

“Our goal with RxPONDER was to better understand when to use adjuvant chemotherapy to enable personalized treatment instead of a one-size-fits-all approach,” said study lead author Kevin Kalinsky, M.D., a long-time SWOG investigator and director of the Glenn Family Breast Center at the Winship Cancer Institute of Emory University. “These practice-changing results definitively show that postmenopausal women with this common form of breast cancer can be spared unnecessary chemotherapy and receive only hormone therapy, potentially saving tens of thousands of women the time, expense and harmful side effects that can be associated with chemotherapy. For the women diagnosed with breast cancer prior to menopause who may benefit from chemotherapy, the data help individualize the discussion of risk and benefit of chemotherapy.”

Based on the RxPONDER results, the National Comprehensive Cancer Network® (NCCN®)v updated its guidelines for breast cancer and recognized the Oncotype DX Breast Recurrence Score test as the only test that can be used for prediction of chemotherapy benefit in early-stage breast cancer patients with 1 to 3 positive axillary lymph nodes, including The Oncotype DX test is now the only test classified as “preferred” with the highest level of evidence for node-negative and postmenopausal node-positive (1 to 3 positive nodes) patients. In addition, NCCN recommends considering the test to assess prognosis in premenopausal node-positive patients who are candidates for chemotherapy.

“The RxPONDER results, together with the foundational TAILORx resultsvii in node-negative, early-stage breast cancer, further elevate the test to a standard of care, supporting its inclusion in guidelines as well as its reimbursement and adoption on a global scale,” said Rick Baehner, M.D., chief medical officer of Precision Oncology at Exact Sciences. “Now with the RxPONDER results, many more women worldwide may be able to receive hormone therapy alone, avoiding the negative side effects of chemotherapy without increasing the risk of cancer returning.”

One of the largest clinical trials in node-positive, HR-positive, HER2-negative early breast cancer, RxPONDER enrolled more than 5,000 women with up to three positive nodes. The prospective, randomized Phase III study was conducted at 632 sites in nine countries – the United States, Canada, Mexico, Colombia, Ireland, France, Spain, South Korea and Saudi Arabia. Women with a Recurrence Score result of 0 to 25 were randomized to treatment with hormone therapy alone or chemotherapy followed by hormone therapy. Randomized patients were stratified based on their Recurrence Score result, menopausal status and type of lymph node surgery. Further analyses and additional patient follow up are planned by the SWOG investigators.