Evista: Help for Breast Cancer, Heart?
Researcher Says Study on Benefits for Osteoporosis Drug Are 'Disappointing'
July 12, 2006 -- Hopes that the osteoporosis
drug Evista would offer women a clearly safer alternative to tamoxifen for
prevention have been dashed by findings from a long-awaited study, researchers
The postmenopausal women in the trial all had risk factors for coronary
and were considered at risk for heart attack and stroke.
Women who took Evista did develop significantly fewer breast cancers than
women randomly assigned to take a placebo (medicine-free treatment) in the
approximately five-year study. But they also had significantly more fatal
strokes and potentially dangerous blood clots.
Researchers concluded that the benefits of Evista for preventing
osteoporosis and breast cancer have to be weighed
against the risk of stroke and blood clots on a case-by-case basis.
The study appears in tomorrow's issue of the New England Journal of
Medicine. It was funded, in part, by Evista manufacturer Eli Lilly. Eli
Lilly is a WebMD sponsor.
"This study highlights the fact that we cannot look at one condition or
one outcome when we consider a drug for prevention," says Lori Mosca, MD,
PhD, researcher on the "Raloxifene Use for the Heart" (RUTH) study.
Mosca tells WebMD that she considers the findings "somewhat
"This trial was pretty much a wash in terms of benefits vs. risks in
this population [at high risk for cardiovascular events]," she says.
"The bar has to be higher for drugs used for prevention of diseases than
for drugs used to treat them. I think there needs to be a clear indication of
No Heart Benefits
As the name suggests, the original goal of the RUTH trial was to determine
if Evista could help prevent heart attacks and strokes in women at high risk
Evista is in a class of drugs known as selective estrogen receptor
modulators (SERMs). Tamoxifen, which is also a SERM, is approved for breast
cancer prevention in high-risk women and for the treatment of breast
A total of 10,101 postmenopausal women with multiple risk factors for heart
disease participated in the RUTH trial; roughly half took Evista every day for
an average of five years and the other half unknowingly took an
The number of cardiac events experienced by the two groups was similar. But
significantly fewer breast cancers were diagnosed in the Evista users than in
those on placebo (40 vs. 70).
Deaths from any cause were also similar in both groups, and the two groups
had roughly the same number of strokes. But Evista users had significantly more
fatal strokes (59 vs. 39) and potentially dangerous blood clots (103 vs. 71
events) than women taking placebo.
Mosca points out that women taking the SERM also had a higher incidence of
several nonlife- threatening, but troubling, side effects, including hot
flashes and leg cramps.