Pradaxa Label Update May Increase Use Over Warfarin, Despite Risks

Federal drug regulators are allowing a label update for the controversial anticoagulant Pradaxa, which may increase use of the medication over Coumadin (warfarin), despite hundreds of deaths and thousands of reports involving bleeding problems from Pradaxa over first two years it has been on the market. 

The new Pradaxa label update was announced by Boehringer Ingelheim on June 6, indicating that new information will be added to the label that suggests Pradaxa is better than warfarin at reducing the risk of ischemic and hemorrhagic strokes. The new label information is based on data from clinical trials known as RE-LY, which were used to obtain FDA approval to market the medication in October 2010.

The claims that the drug is superior to warfarin will appear in the Clinical Studies section of the drug’s label. However, the same trial has come under fire from critics, who have suggested that the RE-LY study was fundamentally flawed, and that the medication never should have been approved based on the trials results.

According to a letter published last year in the Therapeutics Initiative (PDF), researchers from the University of British Columbia criticized the study, indicating that it allowed bias and errors to creep into the results. While the trial used a double-blind method of comparison between the two doses of Pradaxa, a non-blinded comparison was used between Pradaxa and warfarin.

Pradaxa (dabigitran) was introduced as the first alternative to Coumadin (warfarin) for the prevention of stroke among patients with atrial fibrillation. However, the drug quickly earned a darker reputation after it became associated with reports of uncontrolled hemorrhaging and bleeding deaths.

While bleeding problems that develop with use of Coumadin can be reversed through a dose of Vitamin K, which can be given to patients to stop the drug’s anticoagulation effects, no such reversal agent is available for Pradaxa users. Therefore, doctors are often left unable to stop bleeding, often resulting in serious injury or death.

The new Pradaxa label update was announced just days after a report by the Institute for Safe Medication Practices (ISMP) found that problems with Pradaxa topped the FDA’s list for most adverse event reports in 2011. The ISMP quarterly MedWatch report found that among adverse event reports submitted to the FDA last year, Pradaxa was identified as the cause for 542 patient deaths in the United States and more cases of severe hemorrhage than any other medication, including warfarin.

Boehringer Ingelheim faces a growing number of lawsuits over Pradaxa brought on behalf of individuals who suffered serious or fatal injuries due to uncontrollable bleeding while taking the medication. According to allegations raised in the complaint, the drug maker recklessly promoted the medication as superior to warfarin without adequately warning consumers or the medical community about the lack of reversal agent or risk of serious bleeding events.