Anastrozole and fulvestrant combo better than single drug for metastatic breast cancer

August 1, 2012

Results of a SWOG clinical trial published August 2 in the New England Journal of Medicine show the combination of anastrozole and fulvestrant extended the median survival time of women with hormone receptor-positive metastatic breast cancer by more than six months compared to women treated with a standard therapy of anastrozole alone (47.7 months vs 41.3 months).

The combination therapy also lengthened the median time to disease progression for these patients (15 months vs 13.5 ). Progression-free survival time was the primary endpoint measured in the trial; overall survival time was a secondary endpoint.

"The combination offers a new standard for first-line treatment of postmenopausal women with hormone receptor-positive ," says lead investigator on the study Rita Mehta, M.D., of the University of California, Irvine Medical Center. "It has been many years since these patients have seen a new treatment that can significantly extend their overall survival time."

(Arimidex) and fulvestrant (Faslodex), the anti-estrogen drugs included in the SWOG S0226 trial, are both already used in treating breast cancer, though not in combination. Anastrozole suppresses the body's production of tumor-promoting estrogen, while fulvestrant not only blocks the receptors that estrogen uses to drive to grow and reproduce, but also accelerates the degradation of these receptors. Mehta and her colleagues hypothesized that these two different modes of action together could make the combination more effective than either alone against hormone receptor-positive breast cancer, the subtype seen in more than one half of all cases of breast cancer.

The paper also reports that 41 percent of patients on the anastrozole-only arm switched to fulvestrant treatment after their disease progressed on anastrozole, suggesting that combined use of the two agents rather than the sequential use underlies the impressive seen in the study.

Earlier results of the trial, which enrolled 707 postmenopausal patients at 73 U.S. institutions, were presented at a professional meeting in December 2012. The article reports additional data.

The researchers note that they saw improvement in survival in spite of the fact that the dose of fulvestrant used in the trial – 250 mg monthly – was only half of what the accepted standard is today, and in spite of the fact that the control arm performed better than projected in the design of the study. They recommend that future clinical trials compare the combination of high-dose fulvestrant and an aromatase inhibitor such as anastrozole against each of the drugs alone.

Explore further: Anti-estrogen combo better than single drug for hormone-sensitive breast cancer

More information: Mehta RS, Barlow WE, Albain KS, et al. "Combination Anastrozole and Fulvestrant in Metastatic Breast Cancer." New England Journal of Medicine 367(5): 37-46, 2012.

Related Stories

Anti-estrogen combo better than single drug for hormone-sensitive breast cancer

December 7, 2011
Post-menopausal women with hormone receptor-positive metastatic breast cancer may have a new treatment option that could lengthen their lives, according to results of a study by the SWOG clinical trials network that were ...

New hope for advanced post-menopausal breast cancer patients resistant to hormonal therapy

September 26, 2011
Results from a phase III clinical trial have shown that combining two existing cancer drugs to treat post-menopausal women with advanced breast cancer resistant to hormonal therapy significantly improves outcome. Researchers ...

Estrogen-targeting drug combo may help prevent lung cancer

January 9, 2012
A combination of drugs that target estrogen production significantly reduced the number of tobacco carcinogen-induced lung tumors in mice, according to results from a preclinical study.

Combination of everolimus and exemestane improves survival for women with metastatic breast cancer

December 8, 2011
In an international Phase III randomized study, everolimus, when combined with the hormonal therapy exemestane, has been shown to dramatically improve progression-free survival, according to research from The University of ...

New clinical trial to test novel approach to treat triple-negative breast cancer

June 2, 2011
A multicenter clinical trial led by a researcher at the University of Maryland Marlene and Stewart Greenebaum Cancer Center will evaluate a new approach to treat triple-negative breast cancer, an often-aggressive type of ...

Recommended for you

Lung cancer triggers pulmonary hypertension

November 17, 2017
Shortness of breath and respiratory distress often increase the suffering of advanced-stage lung cancer patients. These symptoms can be triggered by pulmonary hypertension, as scientists at the Max Planck Institute for Heart ...

Researchers discover an Achilles heel in a lethal leukemia

November 16, 2017
Researchers have discovered how a linkage between two proteins in acute myeloid leukemia enables cancer cells to resist chemotherapy and showed that disrupting the linkage could render the cells vulnerable to treatment. St. ...

Computer program finds new uses for old drugs

November 16, 2017
Researchers at the Case Comprehensive Cancer Center at Case Western Reserve University School of Medicine have developed a computer program to find new indications for old drugs. The computer program, called DrugPredict, ...

Pharmacoscopy improves therapy for relapsed blood cancer in a first clinical trial

November 16, 2017
Researchers at CeMM and the Medical University of Vienna presented a preliminary report in The Lancet Hematology on the clinical impact of an integrated ex vivo approach called pharmacoscopy. The procedures measure single-cell ...

Wider sampling of tumor tissues may guide drug choice, improve outcomes

November 15, 2017
A new study focused on describing genetic variations within a primary tumor, differences between the primary and a metastatic branch of that tumor, and additional diversity found in tumor DNA in the blood stream could help ...

A new strategy for prevention of liver cancer development

November 14, 2017
Primary liver cancer is now the second leading cause of cancer-related death worldwide, and its incidences and mortality are increasing rapidly in the United Stated. In late stages of the malignancy, there are no effective ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.