(Ivanhoe Newswire) -- A new drug cocktail might be the right mix to fight
breast cancer after it becomes resistant to standard therapy.
The standard treatment for breast cancer is anti-hormonal medicines, such as
aromatase inhibitors (AIs), which lower the amount of estrogen in the body. Over
time, however, the cancer figures out a way to thrive without the estrogen. The
new strategy to fight this resistance combines an aromatase inhibitor with
sorafenib, an FDA-approved oral medication used to treat liver and kidney
cancers.
"We believe the sorafenib might disrupt the machinery created by the tumor to
grow without the estrogen," presenting author Claudine Isaacs, M.D., clinical
director of breast cancer program at Georgetown Lombardi Comprehensive Cancer
Center, was quoted as saying.
"After the machinery is destroyed, the aromotase inhibitor can do its work
again," she explained. "We're already seeing some encouraging responses to this
approach."
The study involved 35 post-menopausal women with metastatic breast cancer
resistant to aromotase inhibitors. The women continued taking an aromotase
inhibitor for the study, but they also took sorafenib. Twenty percent of the
women had a complete or partial response, including those who had stable disease
for at least 6 months.
Isaacs said this finding suggests that sorafenib is acting to reverse resistance
to AIs, as this type of response would not have been expected with either
sorafenib alone or with continuing the AI. She concluded, "To manage breast
cancer long term, it's apparent that we may need to continually switch drugs to
keep up with how a cancer evolves and evades each approach."
SOURCE: Presented at the CTRC-AACR San Antonio Breast Cancer Symposium, December
9 - 13, 2009
