Rx Busts Clots with Less Bleeding

Venous thromboembolism treated with dabigatran had less bleeding side effects compared to warfarin

/ Author:  / Reviewed by: Robert Carlson, M.D

(RxWiki News) Blood clots are very serious business that require treatment. But clot-busting medication can sometimes cause bleeding problems. Fortunately, a new medication may reduce bleeding side effects. 

Venous thromboembolism is caused by a blood clot in a vein, usually in the leg or hip area. The danger is that the blood clot can break free and travel to the the lungs. Once in the lungs, the clot can cause many medical problems, including death or cardiac arrest. 

Anticoagulant medication, such as warfarin (brand names Coumadin and Jantoven), is typically used to treat venous thromboembolism. A side effect of this medicine is bleeding and the patient has to be frequently monitored through blood tests. 

"Talk to a doctor about options for treating your blood clots"

A new medication called dabigatran (brand name Pradaxa) also keeps the blood from clotting but patients taking this type of medication do not need constant monitoring. 

A recent study found that dabigatran was an effective long-term treatment for venous thromboembolism and carried a lower risk of bleeding compared to warfarin.  

Sam Schulman, MD, of Department of Medicine, McMaster University in Ontario, led a team of researchers to compare dabigatran to warfarin or placebo (fake pill) in patients who had venous thromboembolism for at least three months. 

Patients were divided into groups based on the medication they received. There were 1,430 patients in the dabigatran group, 1,426 in the warfarin group and 681 in the placebo group. 

Warfarin medicine is a vitamin K antagonist and works by blocking the body's ability to produce clotting factors that are vitamin K dependent. Dabigatran also keeps the blood from clotting by acting as a thrombin (important enzyme in the body) inhibitor. 

Researchers first compared the effects of dabigatran to those of warfarin on several health outcomes, including recurring venous thromboembolism, major bleeding (death or into a critical organ), major or clinically relevant bleeding (any bleeding problems requiring medical care) and acute coronary syndrome (obstruction of heart arteries). 

Results showed that recurrent venous thromboembolism occurred in 1.8 percent of the dabigatran group compared to 1.3 percent of the warfarin group. Major bleeding was seen in 0.9 percent of the dabigatran group versus 1.8 percent of the warfarin group. 

Major or clinically relevant bleeding was found in 5.6 percent of the dabigatran group compared to 10.2 of the warfarin group. Acute coronary syndrome was seen in 0.9 percent of dabigatran group and 0.2 percent of warfarin group. 

Researchers also looked at dabigatran compared to the placebo group on the same health outcomes mentioned above.

Results showed that recurrent venous thromboembolism occurred in 0.4 percent of the dabigatran group compared to 5.6 percent of the placebo group. Major bleeding occurred in 0.3 percent of dabigatran group and 0 percent of the placebo group. 

Major or clinically relevant bleeding was found in 5.3 percent of the dabigatran group and 1.8 percent of the placebo group. Acute coronary syndrome was seen in one patient in both the dabigatran and placebo group. 

The study results showed that dabigatran was an effective long-term treatment for venous thromboembolism. Patients taking dabigatran had a lower risk of bleeding compared to warfarin. Dabigatran did have a higher risk of bleeding compared to a placebo. 

This study, titled "Extended Use of Dabigatran, Warfarin, or Placebo in Venous Thromboembolism," was published in the New England Journal of Medicine. It was funded by Boehringer Ingelheim; RE-MEDY and RE-SONATE pharmaceutical companies that manufacture dabigatran and warfarin.

Reviewed by: 
Review Date: 
February 19, 2013
Last Updated:
February 27, 2013