Like other anticoagulant medications, the blood thinner Pradaxa comes with a risk of excessive bleeding.

The question of whether the blood thinner Pradaxa is truly safe has been at the heart of thousands of related products liability lawsuits against Boehringer Ingelheim, Pradaxa’s manufacturer.

Pradaxa, also known as dabigatran, was originally approved by the FDA in 2010. It sees widespread use in patients with atrial fibrillation, as a means of reducing their risk of stroke and systemic embolism.

Patients with atrial fibrillation are at particular risk for blood-clot related injuries like stroke.

Atrial fibrillation causes alterations in the heart’s rhythm that can allow clots to form within the heart. These clots may travel to the blood vessels in the brain, potentially causing a stroke.

The blood thinner Pradaxa and other anticoagulant medications are very effective at reducing the risk of stroke for atrial fibrillation patients.

However, the flip side of these medications’ anticoagulant effect is the fact that they can cause excessive bleeding that is difficult to control.

Hundreds of instances of hemorrhages and gastrointestinal bleeds have been reported in association with Pradaxa treatment.

In rare cases, these bleeding injuries have been fatal.

The Fight Over Blood Thinner Pradaxa

Whether Pradaxa is truly safe has been the question at the center of a substantial amount of products liability litigation.

Plaintiffs have cited the results of clinical trials used to gain FDA approval as evidence that Pradaxa is a “defective and unreasonably dangerous.”

For example, one clinical study known as the RE-LY trial compared the effects of Pradaxa to those of warfarin.

Researchers in that trial found Pradaxa patients had a higher rate of gastrointestinal bleeds and a similar rate of major bleeds compared to those who took warfarin.

Reports of major bleeding events in the RE-LY clinical trial spurred an FDA investigation in December 2011.

Plaintiffs also cite aftermarket reports of adverse events that were allegedly associated with Pradaxa.

Manufacturer Boehringer Ingelheim allegedly reported a minimum of 260 fatal bleeding events associated with blood thinner Pradaxa between March 2008 and October 2011.

They also cite a report by the Institute for Safe Medication Practices. That report states that in the first quarter of 2011, Pradaxa was implicated in 932 reports of serious adverse drug events of all types, including 120 patient deaths and 543 cases requiring hospitalization.

Thousands of federal lawsuits over blood thinner Pradaxa were ultimately consolidated in a single multidistrict litigation, or MDL, in a federal court in Illinois.

In addition to challenging the safety of Pradaxa, plaintiffs also alleged that manufacturer Boehringer Ingelheim had failed to adequately warn them about the risks of bleeding associated with Pradaxa.

They also accuse Boehringer Ingelheim of improperly marketing Pradaxa as safer and more convenient than warfaring, despite study results showing that Pradaxa caused some bleeding events more frequently than warfarin.

In May 2014, Boehringer Ingelheim agreed to settle all 4,000 existing Pradaxa lawsuits for a total of $650 million.

That settlement did not foreclose new plaintiffs from bringing new claims over Pradaxa, and further litigation over Pradaxa side effects could still be in Boehringer Ingelheim’s future.