SUNDAY, July 24 (HealthDay News) -- For patients suffering chest
pain, adding a new anti-clotting drug, Eliquis, to dual
antiplatelet therapy may result in severe bleeding without reducing
the risk of heart attack and stroke, a new study finds.
A trial evaluating the combination treatment was halted early
when the risk of severe bleeding among those taking Eliquis
(apixaban) became apparent.
"It is very clear there is an increased risk of bleeding, and in most patients it doesn't appear there is a lot of benefit to outweigh the risk of bleeding," said researcher Dr. John H. Alexander, co-director of cardiovascular research at the Duke Clinical Research Institute of Duke University Medical Center in Durham, N.C.
"We know high-risk patients with acute coronary syndromes continue to have events, and we know antiplatelet therapy is effective," said Alexander. The researchers expected to see some increase in bleeding when they added Eliquis to other anti-clotting therapy, but the bleeding was significant and "there was nothing to offset that increase in bleeding, so we stopped the trial," he said.
The conclusion: "Combination treatment with an anticoagulant and
dual antiplatelet therapy should be avoided unless there is a clear
indication for both, as in some patients with atrial fibrillation,"
The report was published online July 24 in the
New England Journal of Medicine to coincide with presentation
of the study results at the International Society on Thrombosis and
Haemostasis Congress, July 23-28 in Kyoto, Japan.
For the study, researchers randomly assigned 7,392 patients who
were receiving standard antiplatelet therapy with two drugs to an
additional 5 milligrams of Eliquis or a dummy pill twice daily. The
study was double-blind, meaning that neither the patients nor the
researchers knew who was taking Eliquis or a dummy pill.
Eliquis is a so-called Xa inhibitor, which is a class of
anticoagulants that work by blocking factor X, a protein involved
in blood clotting.
Over an average follow-up of eight months, 7.5 percent of the
patients receiving Eliquis had a heart attack, suffered a stroke,
or died, as did 7.9 percent of the patients receiving placebo, the
In addition, 1.3 percent of those taking Eliquis had major
bleeding, compared with 0.5 percent of those receiving the placebo,
Moreover, more patients taking Eliquis had bleeding into the
brain and died from uncontrollable bleeding than patients receiving
placebo, Alexander said.
Would a lower dose of Eliquis work? Alexander is skeptical.
While it could reduce the risk of bleeding, he said he doubts more
heart attacks, strokes or deaths would be prevented.
The trial was funded by Pfizer/Bristol-Myers Squibb, the makers
Commenting on the study, Dr. Gregg C. Fonarow, a professor of
cardiology at the University of California, Los Angeles, said that
"each year more than 1.4 million men and women are admitted to
hospitals in the United States with acute coronary syndromes."
Despite conventional therapy, patients with acute coronary
syndromes remain at risk for recurrent cardiovascular events,
A number of medications that prevent blood clots (known as
antithrombotic drugs) "are being evaluated in patients with acute
coronary syndromes to determine if they can further reduce
cardiovascular event risk without substantially increasing the
bleeding risk when added to conventional therapies," he said.
Apixaban and two other drugs, rivaroxaban (Xarelto) and
dabigatran (Pradaxa), have been shown to provide significant
benefit in reducing stroke and clots in patients with atrial
fibrillation, where the benefit outweighs the bleeding risk,
"However, this new study suggests that the use of apixaban, at least at the dose studied, should be avoided in patients with recent acute coronary syndromes being treated with dual antiplatelet therapy," he said.
For more information on heart disease, visit the
Centers for Disease Control and Prevention.