Skip to content

    Breast Cancer Health Center

    Font Size

    Femara vs. Tamoxifen for Breast Cancer

    Femara, Tamoxifen Show Equal Survival Rates in Breast Cancer Study
    WebMD Health News
    Reviewed by Louise Chang, MD

    Aug. 19, 2009 -- Breast cancer patients may do as well with the drug Femara as they do with tamoxifen, a new study shows.

    The international study, published in The New England Journal of Medicine, included more than 6,100 postmenopausal women who had breast cancer that was sensitive to the hormones estrogen or progesterone.

    After the women finished their breast cancer treatment, they were assigned to one of the following plans:

    • Take tamoxifen for five years
    • Take Femara for five years
    • Take tamoxifen for two years, then Femara for three years
    • Take Femara for two years, then tamoxifen for three years

    The women didn't know which pills they were taking.

    Tamoxifen and Femara work differently. Tamoxifen blocks the action of estrogen in the body.

    Femara belongs to a class of drugs called aromatase inhibitors. Those drugs, which also include Arimidex and Aromasin, target the aromatase enzyme, which is needed to make estrogen.

    The new study shows that over about six years, the women's odds of cancer-free survival were equally good taking Femara alone or taking either tamoxifen first and Femara later or vice versa.

    There was no significant difference in overall survival between women who took Femara alone compared to women who took tamoxifen alone for five years, report the researchers, who included Henning Mouridsen, MD, chair of the Danish Breast Cancer Cooperative Group.

    In 2005, the researchers reported that recurrence of breast cancer in sites far from the breast was less common in women taking Femara than in those taking tamoxifen.

    The new study shows that the drugs' side effects were in line with known risks; no unusual adverse events were reported.

    The study was funded by Novartis, the drug company that makes Femara. In the journal, Mouridsen and several other researchers disclose ties to Novartis. Femara was the only aromatase inhibitor included in the study.

    Today on WebMD

    Breast Cancer Overview
    From mammograms to living after treatment.
    Dealing with breast cancer
    Get answers to your questions.
    woman having mammogram
    The 3 latest tips to know.
    woman undergoing breast cancer test
    Most abnormalities aren’t breast cancer.
    Resolved To Quit Smoking
    Breast Cancer Treatments Improving
    Woman getting mammogram
    Screening Tests for Women
    serious woman
    Pink badge on woman chest to support breat cancer
    what is your cancer risk
    breast cancer survivors