Higher Doses of Pradaxa Slightly More Likely to Cause Bleeding: Study

A long-term study of Pradaxa found that around 3% of all Pradaxa users could expect to face at least one major bleeding event per year, with those taking the 150 mg dose at slightly higher risk.

While Boehringer Ingelheim, the makers of Pradaxa, are touting the findings of the study published in the American Heart Association’s Circulation journal as proof of the drug’s safety profile, many concerns have been expressed that Pradaxa bleeding events are more dangerous than those caused by older blood thinners because there is no antidote to control the hemorrhages.

The study comes as the company pushes for expanded approval to use of Pradaxa in Europe for treatment and prevention of blood clot-related problems, such as deep vein thrombosis and pulmonary embolism. If approved, it could increase the number of Pradaxa-using patients by several million. The company has not yet made a similar push for such approval in the U.S.

Concerns over Pradaxa Bleeding Problems

The findings of the long term study, RE-LY, indicate that 3.74% of patients who take Pradaxa 150 mg for a year are likely to experience major hemorrhaging. Those taking 110 mg Pradaxa faired marginally better, at 2.99% risk of a major bleeding event. About 3.02% of those taking the 110 mg dose died per year, compared to 3.1% taking the higher dose.

Researchers concluded that Pradaxa 150 mg twice daily had a higher rate of major bleeding than the lower dose and about the same death rate. However, Boehringer Ingelheim heralded the findings as proof of the drug’s long-term safety profile in a press release.

Pradaxa (dabigatran) was the first member of a  new class of anticoagulants, which was introduced in October 2010 as a stroke prevention alternative to warfarin, which is more commonly known as Coumadin.

Boehringer Ingelheim has aggressively promoted Pradaxa as superior to warfarin, because it requires less monitoring. However, a concerning number of reports have been filed since the drug was introduced involving patients who suffered uncontrollable bleeding problems with Pradaxa.

Unlike warfarin, which has a reversal agent that can be used to stop bleeding problems, Pradaxa has no antidote and doctors are often unable to reverse the blood thinning effects of the medication if a user develops a hemorrhage.

Several hundred Pradaxa lawsuits are currently pending against Boehringer Ingelheim, which were brought by individuals who allege that the drug maker failed to adequately warn about the bleeding risk or the lack of a reversal agent for Pradaxa, which could allow doctors to control bleeding that may develop while the medication is used.