New Menopause Medication Potentially Prevents Breast Cancer While Alleviating Hot Flashes

A medication originally designed to alleviate menopause symptoms could also play a significant role in preventing breast cancer, according to new research conducted at Northwestern University in Illinois. Scientists found that Duavee, a drug manufactured by Pfizer, was able to “significantly reduce” the growth of breast tissue cells—a key factor associated with the development and progression of cancer.

During a phase 2 clinical trial, researchers enrolled 141 post-menopausal women who had been diagnosed with ductal carcinoma in situ (DCIS), which is categorized as stage 0 breast cancer. This non-invasive form of the disease currently affects over 60,000 women in the United States every year and can ultimately lead to invasive breast cancer if not managed appropriately.

In the trial, participants were divided into two groups: one group received Duavee, while the other was given a placebo for a month prior to undergoing breast surgery. Duavee is a conjugated estrogen/bazedoxifene (CE/BZA) drug that blends estrogen with bazedoxifene to help reduce the typical side effects associated with estrogen therapy.

Dr. Swati Kulkarni, lead investigator and professor of breast surgery at Northwestern University Feinberg School of Medicine, remarked that the most significant finding was CE/BZA’s ability to slow the proliferation of cells in milk ducts of DCIS patients who expressed the estrogen receptor, compared to the placebo group. Notably, the quality of life remained comparable between both groups during treatment, although those taking the drug reported fewer hot flashes—an expected side benefit since Duavee is already FDA-approved for this menopausal symptom.

These groundbreaking results were recently presented at the American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago. However, the findings are still considered preliminary and have yet to be published in a peer-reviewed medical journal.

“What excites me most is that a medication designed to help women feel better during menopause may also reduce their risk of invasive breast cancer,” said Dr. Kulkarni, who also practices as a breast surgeon. She highlighted that women facing a higher risk of breast cancer—such as those with high-risk lesions and concurrent menopausal symptoms—would likely benefit the most from this drug. Traditionally, these women are advised against standard hormone therapies, leaving them with limited options to manage menopausal discomfort.

The research team remains optimistic but cautious about Duavee’s future as a breast cancer prevention tool. “Our findings suggest that CE/BZA may prevent breast cancer, but larger studies with several years of follow-up are needed before we would know this for sure,” Dr. Kulkarni stated.

Other experts in the field are expressing interest, but also urge restraint given the early nature of the data. Dr. Sheheryar Kabraji, chief of breast medicine at a major cancer center in New York, emphasized that more research will be required before conclusively determining CE/BZA’s effectiveness at preventing invasive breast cancer or reducing overall risk. Kabraji pointed out that the current trial focused on reducing levels of a specific protein, which does not necessarily guarantee lower recurrence rates or prevention of more advanced disease. Nonetheless, she noted that the absence of adverse changes in quality of life and improvements in symptoms such as hot flashes make this therapy an attractive option for further exploration.

Lead researcher Dr. Kulkarni stressed that this medication should not be used for treating invasive breast cancer or DCIS itself. “Right now, we can say that women who are concerned about their risk of developing breast cancer can consider this medication to treat their menopausal symptoms,” she concluded, adding that more comprehensive studies will be crucial before Duavee becomes a standard preventive therapy for breast cancer.