Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New stroke-prevention drug unlikely to be cost-effective except in patients at high risk of bleeding

09.02.2005


A new study has shown a stroke-prevention drug designed to be an improvement over prior treatments is less cost-effective for most patients than warfarin, the blood thinner with a 50-year history of helping prevent blood clots and strokes. The study, conducted by researchers at Washington University School of Medicine in St. Louis found, however, that the new drug would be cost-effective for those atrial fibrillation patients whose risk of bleeding is high. The findings are reported in the February 9 issue of the Journal of the American Medical Association.



In patients with atrial fibrillation, the upper part of the heart often quivers instead of beating, so blood pools and clots in the upper chambers. The blood clots tend to be large and can travel to the brain causing massive strokes.

AstraZeneca, the company that developed Exanta, had submitted a New Drug Application to the Food and Drug Administration for approval of the drug as an agent to prevent strokes in patients with atrial fibrillation as well as to prevent blood clots in other conditions. The drug was intended as an alternative to warfarin.


In October 2004, the FDA denied Exanta approval. The agency noted that Exanta carried a small risk of liver damage and cited insufficient evidence that it was as effective as warfarin for preventing strokes. "Warfarin is extremely effective," says lead author Brian F. Gage, M.D., associate professor of medicine. "It lowers the risk of stroke by 65 percent. Unfortunately, patients have different sensitivities to warfarin, so it’s difficult to adjust the dose, especially when initiating the drug. While they’re on warfarin, patients’ blood clotting has to be monitored often, and patients find that inconvenient. Warfarin also interacts with various foods and other drugs. Moreover, it doubles the risk of hemorrhage."

Before Exanta, the alternative for patients unable to tolerate warfarin was aspirin, which is not nearly as good as warfarin at preventing blood clots and strokes. "Physicians would like to have a drug that’s as effective as warfarin but doesn’t require monitoring and is less likely to cause bleeding," Gage says. "That’s why there was so much interest in Exanta--it reduces the risk of major hemorrhage by 26 percent and doesn’t have warfarin’s interactions or dosing problems."

The current study was undertaken to provide physicians with a rational way to choose among the three potential therapies. "Since each drug has its own drawbacks, trying to compare them was like comparing apples and oranges," Gage says. "We needed a common currency to make the comparison, so we accounted for quality of life factors and analyzed the way each drug affected quality-adjusted survival."

Gage and Washington University medical student Cara O’Brien compiled data from patients with atrial fibrillation and from the doctors that treated them, adjusting their ranking of each drug based on quality of life measures. They quantified the risk for adverse health conditions such as mild, moderate or severe stroke and looked at other factors that affect quality of life such as the need for multiple tests and ease of taking the medication.

O’Brien and Gage found that warfarin and Exanta were equivalent for preventing strokes and both were better than aspirin. The difference in quality of life measures among the three drugs was small. However, because of its higher price, Exanta was not cost-effective for most patients: the small gain in quality of life did not make up for the higher price in patients at low risk of bleeding.

On the other hand, the study showed that in patients with a high risk of bleeding as well as a significant risk of stroke, Exanta could increase quality of life and thereby increase its cost-effectiveness to a level that is acceptable by current U.S. health-care standards. "We have a lot of octogenarians with atrial fibrillation and a high risk of bleeding, for example, because they tend to fall, have kidney disease or are taking anti-inflammatory medicine," Gage says. "In fact, close to a million Americans with atrial fibrillation are at relatively high risk for hemorrhage. For many of these people, Exanta would be cost-effective."

Exanta has been approved for use in about ten European countries, and observers believe AstraZeneca may soon appeal the FDA’s original ruling and again seek approval for the drug in the U.S.

Gwen Ericson | EurekAlert!
Further information:
http://www.wustl.edu

More articles from Studies and Analyses:

nachricht Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Salmonella as a tumour medication

HZI researchers developed a bacterial strain that can be used in cancer therapy

Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Shrews shrink in winter and regrow in spring

24.10.2017 | Life Sciences

Microfluidics probe 'cholesterol' of the oil industry

23.10.2017 | Life Sciences

Gamma rays will reach beyond the limits of light

23.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>