Quick-reversal method may be at hand for new blood thinner

Quick-Reversal method may be at hand for new blood thinner
Drugs like apixaban have advantages, but risk for bleeding requires rapid antidote, researchers say.

(HealthDay) -- Newer blood-thinning drugs sometimes have one drawback: In cases where they trigger bleeding, their effects can be tough to reverse compared to the standard anticoagulant, warfarin.

Now, a new study finds there are three different approaches to reverse the action of one new blood thinner, apixaban (Eliquis) -- a drug that's currently under review by the U.S. Federal Drug Administration.

Researchers in Spain noted that it remains unclear which method for reversing this new drug might be best.

"If you have an accident or need , doctors have three ways to reverse [the older, standby blood-thinner] that work in a matter of minutes to hours. In contrast, there is little information on how best to reverse the effects of newer anticoagulants, which can take 10 to 18 hours," study author Dr. Gines Escolar, an associate professor of hematology at the University of Barcelona, explained in an news release.

Newer blood thinners, such as apixaban and rivaroxaban [Xarelto, already FDA-approved], typically require less frequent blood tests compared to warfarin, have fewer interactions with foods or other medications and have less variation in dosages.

Nevertheless, "despite these advantages, there is one common side effect of all blood thinners that can be severe -- excess bleeding," Escolar explained.

In conducting the study, the researchers added a high dose of apixaban to blood from healthy donors to test the effects of various methods of reversing on the new drug. They found that two blood-clotting agents -- prothrombin complex concentrates and activated prothrombin complex concentrates -- were more efficient than recombinant factor VII in reversing apixaban. Recombinant factor VII, however, was the first to produce a blood clot and was also most effective in studies with blood circulating through a damaged blood vessel.

"The good news is that the various applied indicate that these approaches may reverse the effects of apixaban," Escolar concluded. "But, even with the favorable results in perfusion [restoration of blood flow] studies using a damaged vessel, we're far from knowing what will work best in a bleeding patient. Resolving efficacy and safety issues will require a clinical trial."

One expert in the United States said that determining a quick, safe way of reversing apixaban would be key to its use.

"Apixaban, which is being considered for use in the prevention of stroke and systemic embolism in patients with [the irregular heartbeat] atrial fibrillation, can be an attractive alternative to warfarin and heparin also used in similar patients," said Dr. David Friedman, chief of Heart Failure Services at North Shore-LIJ's Plainview Hospital in Plainview, N.Y.

"The hope would be for these researchers to next show a safe, effective and quick way to clinically reverse the effects of apixaban on patients with atrial fibrillation who come to the ER with a new bleeding event," he said. If such a method of reversal is confirmed, "clinicians may start to feel more comfortable with the advantages of these newer medicines," he said.

Apixaban has already been approved in Europe for preventing in adults after knee or hip replacement surgery. The drug is currently under review by the U.S. to prevent stroke in people with atrial fibrillation.

The study, presented in the American Heart Association's Emerging Science Series, was partially funded by Bristol-Myers Squibb, which is developing apixaban.

More information: The U.S. National Institutes of Health has more about blood thinners.

Related Stories

More advantages found for new drug: study

Feb 10, 2011

New findings from a McMaster University-led study of a drug recently identified to prevent stroke in patients with atrial fibrillation have been published in the high-impact New England Journal of Medicine (NEJM) today. ...

Easy-to-use blood thinners likely to replace Coumadin

Feb 06, 2012

Within a few years, a new generation of easy-to-use blood-thinning drugs will likely replace Coumadin for patients with irregular heartbeats who are at risk for stroke, according to a journal article by Loyola University ...

Success stops drug trial

Aug 31, 2010

The data monitoring committee of the AVERROES study, seeing overwhelming evidence of the success of apixaban in the prevention of stroke in patients with atrial fibrillation who are unsuitable for the conventional treatment ...

Recommended for you

Viagra ads target women for first time

Sep 30, 2014

The maker of the world's top-selling erectile dysfunction drug on Tuesday will begin airing the first Viagra TV commercial in America that targets the less-obvious sufferers of the sexual condition: women.

User comments