Featured Research

from universities, journals, and other organizations

Efficacy and safety of apixaban compared to warfarin for prevention of stroke and systemic embolism

Date:
August 28, 2011
Source:
European Society of Cardiology (ESC)
Summary:
A large-scale trial finds that apixaban, a new anticoagulant drug, is superior to the standard drug warfarin for preventing stroke and systemic embolism in patients with atrial fibrillation. Moreover, apixaban results in substantially less bleeding, and also results in lower mortality. The benefits of apixaban are consistent irrespective of how well warfarin is used at different centers, as measure by "time in therapeutic range."

A large-scale trial finds that apixaban, a new anticoagulant drug, is superior to the standard drug warfarin for preventing stroke and systemic embolism in patients with atrial fibrillation. Moreover, apixaban results in substantially less bleeding, and also results in lower mortality. The benefits of apixaban are consistent irrespective of how well warfarin is used at different centers, as measure by "time in therapeutic range."

The randomized, double-blind clinical trial known as ARISTOTLE randomized 18,201 patients at 1034 clinical sites in 39 countries to apixaban (5mg twice daily) or to warfarin for an average of 1.8 years.

"These are important findings because they show when compared to warfarin, itself a very effective treatment to prevent stroke, apixaban resulted in an additional 21 percent relative reduction in stroke and systemic embolism. It also resulted in a 31 percent relative reduction in major bleeding, as well as an 11 percent relative reduction in overall mortality," says Granger. The better prevention of stroke was statistically significant with P=0.011, the lower rate of major bleeding at P<0.001, and the lower mortality at p=0.047. Hemorrhagic stroke was reduced by about 50%.

Wallentin notes that these benefits are with a drug that has major practical advantages over warfarin: it does not require monitoring and has few interactions with other medications or food. Apixaban was better tolerated than warfarin, with fewer discontinuations. And he stated "the benefits of reducing stroke and lower rates of bleeding were consistent across all major subgroups and despite the heterogeneity that exists in the quality of warfarin use across the world."

The number of events prevented per 1000 people, which indicate absolute risk reduction, were also impressive, says John Alexander, M.D., a study co-author and Duke cardiologist. "Apixaban prevented 6 patients from having a stroke, 15 patients from having major bleeding, and 8 patients from dying. The predominant effect on stroke prevention was on hemorrhagic stroke. Apixaban prevented 4 patients from having hemorrhagic stroke and 2 patients from having an ischemic or uncertain type of stroke."

Atrial fibrillation is a common abnormal heart rhythm that affects more than 2.6 million Americans. It occurs when the heart's electrical activity becomes disorganized, resulting in an irregular heartbeat with ineffective contraction of the upper chambers of the heart. The potential for blood clots to form, and one's risk for stroke, increases as a result.

"There is an enormous unmet need in terms of treatment of patients at risk for stroke associated with atrial fibrillation," says Granger. "Only about half of patients who should be treated are being treated. The disparity exists because warfarin treatment has several limitations."

The results were presented by the co-chairs of the ARISTOTLE trial in two late breaking clinical trial sessions at the European Society of Cardiology in Paris, France, and the main trial results were published simultaneously online in the New England Journal of Medicine. The time in therapeutic range analysis was presented by Lars Wallentin, professor of cardiology and director of the Uppsala Clinical Research Center in Sweden. The main trial results were presented by Christopher B. Granger, professor of medicine at Duke University in Durham, North Carolina, USA.

Warfarin is a vitamin K antagonist that is well documented for its ability to prevent blood clots. Previous studies indicate long-term use of warfarin in patients with atrial fibrillation and other stroke risk factors can reduce stroke by up to 70 percent. However, only about half of patients who could benefit from warfarin actually do. Patients on warfarin must have regular blood tests to monitor and adjust the dose and avoid certain foods and medications that interfere with warfarin's effect. Warfarin also increases bleeding risk including intracranial hemorrhage.

Because of these limitations, doctors and patients have been eagerly awaiting alternative therapies, one of which is currently available, and several others are currently under investigation in large clinical trials.

Apixaban is an oral direct factor Xa inhibitor that showed promise last year when trial findings presented at the European Society of Cardiology showed apixaban patients were 54 percent less likely to have a stroke or blood clot than those who took aspirin. Apixaban and aspirin showed similar risks of major bleeding.

"Our study indicates treatment with apixaban is more effective than warfarin in preventing stroke without the need for anticoagulation monitoring," says Wallentin.

The study also shows apixaban is safer than warfarin, according to Wallentin. "Our findings show a single dose of apixaban accomplishes the same stroke prevention goal as adjusted-dose warfarin with a substantially lower risk of all types of bleeding across different ages, and with lower rates of discontinuation."

The study was coordinated by Uppsala Clinical Research Institute, Sweden and the Duke Clinical Research Institute.

It was funded by Bristol-Myers Squibb, Co and Pfizer Inc.

Additional study authors include: John J. V. McMurray, M.D., Cardiovascular Research Centre, University of Glasgow; Renato Lopes, DCRI; Elaine Hylek, Boston University; Michael Hanna, BMS; Hussein Al-Khalidi, DCRI; Jack Ansell, Lenox Hill Hospital; Dan Atar, Oslo University Hospital; Alvaro Avezum, Dante Pazzanese Institute of Cardiology; M. Bahit, ECLA Estudios Cardiologicos Latinoamerica; Rafael Diaz, ECLA Estudios Cardiologicos Latinoamerica; J. Donald Easton, Brown University; Justin Ezekowitz, University of Alberta; Greg Flaker, University of Missouri Health Care; David Garcia, University of New Mexico; Margarida Geraldes, BMS; Bernard Gersh, Mayo Clinic; Sergey Golitsyn, Russian Cardiology Research Center; Shinya Goto, Tokai University School of Medicine; J. Antonio Gonzalez-Hermosillo; Instituo N de Cardiologia Ignacio Chavez; Stefan Hohnloser, J.W. Goethe University; John Horowitz, University of Adelaide; Puneet Mohan, BMS; Petr Jansky, Motol University Hospital; Basil Lewis, Lady Davis Carmel Medical Center; Jose Lopez-Sendon, La Paz University Hospital; Prem Pais, St. John's Medical College; Alexander Parkhomenko, Institute of Cardiology; Freek Verheugt, Radboud University Nijmegen Medical Centre; Jun Zhu, Fuwai Hospital


Story Source:

The above story is based on materials provided by European Society of Cardiology (ESC). Note: Materials may be edited for content and length.


Journal Reference:

  1. Christopher B. Granger, John H. Alexander, John J.V. McMurray, Renato D. Lopes, Elaine M. Hylek, Michael Hanna, Hussein R. Al-Khalidi, Jack Ansell, Dan Atar, Alvaro Avezum, M. Cecilia Bahit, Rafael Diaz, J. Donald Easton, Justin A. Ezekowitz, Greg Flaker, David Garcia, Margarida Geraldes, Bernard J. Gersh, Sergey Golitsyn, Shinya Goto, Antonio G. Hermosillo, Stefan H. Hohnloser, John Horowitz, Puneet Mohan, Petr Jansky, Basil S. Lewis, Jose Luis Lopez-Sendon, Prem Pais, Alexander Parkhomenko, Freek W.A. Verheugt, Jun Zhu, Lars Wallentin. Apixaban versus Warfarin in Patients with Atrial Fibrillation. New England Journal of Medicine, 2011; 110827230022006 DOI: 10.1056/NEJMoa1107039

Cite This Page:

European Society of Cardiology (ESC). "Efficacy and safety of apixaban compared to warfarin for prevention of stroke and systemic embolism." ScienceDaily. ScienceDaily, 28 August 2011. <www.sciencedaily.com/releases/2011/08/110828101800.htm>.
European Society of Cardiology (ESC). (2011, August 28). Efficacy and safety of apixaban compared to warfarin for prevention of stroke and systemic embolism. ScienceDaily. Retrieved April 25, 2014 from www.sciencedaily.com/releases/2011/08/110828101800.htm
European Society of Cardiology (ESC). "Efficacy and safety of apixaban compared to warfarin for prevention of stroke and systemic embolism." ScienceDaily. www.sciencedaily.com/releases/2011/08/110828101800.htm (accessed April 25, 2014).

Share This



More Health & Medicine News

Friday, April 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
Companies Ramp Up Wellness to Lower Health Costs

Companies Ramp Up Wellness to Lower Health Costs

AP (Apr. 24, 2014) That little voice telling you to exercise, get in shape and get healthy is probably coming from your boss. More companies are beefing up wellness programs to try and cut down their health care costs. (April 24) Video provided by AP
Powered by NewsLook.com
Blood From World's Oldest Woman Suggests Life Limit

Blood From World's Oldest Woman Suggests Life Limit

Newsy (Apr. 24, 2014) Scientists say for the extremely elderly, their stem cells might reach a state of exhaustion. This could limit one's life span. Video provided by Newsy
Powered by NewsLook.com
FDA Wants To Ban Sales Of E-Cigarettes To Minors

FDA Wants To Ban Sales Of E-Cigarettes To Minors

Newsy (Apr. 24, 2014) The Food and Drug Administration wants to crack down on the use of e-cigarettes, banning the sale of the product to minors. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

More Coverage


Apixaban Superior to Warfarin for Preventing Stroke, Reducing Bleeding and Saving Lives, Research Suggests

Aug. 28, 2011 A large-scale trial finds that apixaban, a new anticoagulant drug, is superior to the standard drug warfarin for preventing stroke and systemic embolism in patients with atrial fibrillation. ... read more
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins