New data from the landmark MA-17 study demonstrated a significant 40 per cent reduction in the rate of distant breast cancer recurrences, or metastases, with extended adjuvant (post-tamoxifen) Femara (letrozole) in postmenopausal women with early breast cancer.
These data from the study, coordinated by the National Cancer Institute of Canada Clinical Trials Group, Ontario and supported by Novartis, were presented during the 'Best of Oncology' session at the annual meeting of the American Society of Clinical Oncology (ASCO) in New Orleans.
In this group of trial participants, which comprised approximately 50 per cent of all patients in MA-17, deaths were reduced by a significant 39 per cent vs. placebo. These results from the MA-17 trial indicated that Femara is the first hormonal therapy to demonstrate a survival advantage in any population in the extended adjuvant setting.
Across the entire study population, survival differences did not reach statistical significance in this analysis. The term extended adjuvant describes the period following standard adjuvant treatment with tamoxifen. Even years after breast cancer diagnosis and primary treatment the ongoing risk of breast cancer recurrence and mortality remains significant for all patients.
Extended adjuvant treatment with Femara is the first therapy to effectively address this ongoing risk.
"Overall, the results of MA-17 may provide a new option for postmenopausal women completing standard adjuvant treatment with tamoxifen," said Paul Goss, director of Breast Cancer Prevention and Research, Princess Margaret Hospital, Toronto, Canada. "Treatment with Femara resulted in a marked reduction in the risk of recurrent breast cancer and the occurrence of new breast cancer. Most importantly, treatment with Femara also reduced distant metastases, which are very often fatal." The results showed that Femara significantly lowered the risk of metastases overall by 40%. At the median 2.5 year follow-up, overall survival was unchanged in node-negative patients, but reductions in local recurrences, new primary tumors, and distant recurrences were consistent with those seen in node-positive patients.
Femara, an aromatase inhibitor, is an oral once-a-day first-line treatment for
postmenopausal women with hormone receptor positive or hormone receptor unknown locally advanced or metastatic breast cancer.
Distant metastases are a well-established risk factor for breast cancer death.
At the median 2.5-year follow-up, a survival advantage has now become apparent in those women whose cancer had already spread to lymph nodes at the time of diagnosis (nodepositive).