Anastrozole Receives FDA Priority Review for Early Breast Cancer Indication

The US Food and Drug Administration (FDA)has granted a 6-month priority review status to the supplemental new drugapplication filed by the AstraZeneca corporation for the use of anastrozole(Arimidex) in the adjuvant treatment of early breast cancer in postmenopausalwomen. Priority review status is granted for new drugs or indications thatrepresent a significant improvement in efficacy or safety over existingtreatments.

"AstraZeneca is committed to constantly expanding thetreatment options breast cancer patients have at their disposal to fight thisdisease," said Gerard T. Kennealey, MD, vice president of clinicalresearch, oncology, for AstraZeneca. "The FDA’s granting of priorityreview status for Arimidex as an early breast cancer treatment is an importantmilestone in the history of breast cancer treatment."

ATAC Trial

Priority review status for anastrozole was based on data fromthe ATAC study (Arimidex and Tamoxifen, Alone or in Combination) conducted inmore than 9,300 postmenopausal women with early breast cancer. Early resultsfrom that study showed that anastrozole reduced the risk of disease recurrenceby 17% over tamoxifen as well as the risk of contralateral breast cancer by 58%over tamoxifen.

Current Indications

Anastrozole is currently approved for first-line treatment ofpostmenopausal women with hormone receptor-positive or hormone receptor-unknownlocally advanced or metastatic breast cancer and also for the treatment ofadvanced breast cancer in postmenopausal women with disease progressionfollowing tamoxifen therapy. Common side effects seen in clinical trials haveincluded hot flashes, nausea, asthenia, back and bone pain, and increased cough.Joint pain and stiffness have also been reported.