EAST HANOVER, N.J., Dec. 9, 2010 /PRNewswire/ — A new study
shows that the addition of everolimus (Afinitor® tablets) to
the hormonal therapy tamoxifen in patients with hormone-receptor
positive/human epidermal growth factor receptor 2-negative
(HR+/HER2-) metastatic breast cancer who have been previously
treated with an aromatase inhibitor (AI) delays disease progression
compared to tamoxifen alone. These results were presented today at
the 33rd Annual CTRC-AACR San Antonio Breast Cancer Symposium in
San Antonio, Texas(1).
Findings from a randomized, Phase II study of 111 patients
showed the proportion of metastatic breast cancer patients without
tumor progression at six months was 61.1% for those taking
everolimus plus tamoxifen (95% confidence interval [CI], 46.9 to
74.1) versus 42.1% for patients treated with tamoxifen alone (95%
CI, 29.1 to 55.9); p=0.045(1).
Disease progression was delayed by a median of 8.6 months in
patients treated with the combination versus 4.5 months in patients
treated with tamoxifen alone, with everolimus in combination with
tamoxifen providing a statistically significant reduction in the
risk of disease progression by 47% (hazard ratio=0.53 [95% CI, 0.35
to 0.81]; log-rank test: p=0.0026, exploratory analysis). Side
effects were generally manageable in both study arms. As of October
2010, there were 25 patient deaths in the tamoxifen arm versus nine
in the everolimus plus tamoxifen arm (hazard ratio=0.32 [95% CI,
0.15 to 0.68]; log-rank test: p=0.0019)(1).
This Phase II trial is conducted by the Groupe d’Investigateurs
Nationaux pour l’Etude des Cancers Ovariens et du sein (the French
Everolimus is an investigational agent for the treatment of
patients with breast cancer. Everolimus targets mTOR in cancer
cells, a protein that acts as an important regulator of tumor cell
division, blood vessel growth and cell metabolism(7,8).
“The almost doubling of time to di