Pradaxa Manufacturer Admits to Receiving Reports of Death

For decades, warfarin (brand name Coumadin) was the leading choice of physicians for patients who required a blood-thinning drug, such as those with atrial fibrillation who were at a higher risk for clotting and stroke. In October 2010, however, the FDA approved Pradaxa, a "new-generation" blood thinner that according to initial clinical studies, was superior to warfarin in reducing stroke risk, yet didn't require regular blood tests to check dosage, such as those necessary with warfarin.

Only a few months after approval, however, reports started coming in about serious side effects, including potentially fatal Pradaxa bleeding. All blood-thinning drugs carry some risk of severe bleeding events, but Pradaxa seemed to differ in two ways. First, the events seemed to be happening more than expected, and second, doctors had no readily available antidote to stop the bleeding.

As pressure increased in recent months on drug maker Boehringer Ingelheim, in the form of scientific studies, FDA warnings, and investigations in other countries, the company just recently admitted to receiving more than 260 death reports related to the drug.

Bleeding Events Spur Investigations

In the first quarter of 2011, just shortly after Pradaxa received FDA approval, the Institute of Safe Medication Practices noted in their "QuarterWatch" publication that more than 500 reports of fatal, disabling, and other severe hemorrhages were linked with Pradaxa (dabigatran).

Later that year, in September, New Zealand launched an investigation into the drug after reports of elderly patients dying as a result of internal bleeding, while Japan asked the manufacturer to notify physicians of the risks, and potentially to recommend lower doses for those over 70 years old.

Another May report, given by researchers at the 2012 Thrombosis and Hemostasis Summit of North America in Chicago announced early data showing that in over 2,000 study participants, only .88 percent on warfarin experienced complications, versus 11.5 percent of those taking Pradaxa. Side effects included internal bleeding, heart attack, DVT, and even death.

No available antidote

One of the biggest concerns with the drug is that currently, doctors have no readily available antidote to stop excessive bleeding. In May 2012, an article published in the Journal of Neurosurgery detailed a case of an elderly patient who was treated with Pradaxa for atrial fibrillation, and presented with a "rapidly expanding intracranial hemorrhage" after a ground-level fall. As the doctors were unable to treat the problem effectively enough, the patient died around six hours later.

"There is currently no effective antidote to reverse the anticoagulant effect of dabigatran in the event of an emergency," the authors wrote. "Preclinical and early clinical trials have thus far failed to yield an effective reversal agent for these medications, and new treatments are certainly needed."

FDA Warns of Serious Side Effects

On December 7, 2011, the FDA issued a drug safety communication stating they were evaluating postmarketing reports of serious bleeding events related to Pradaxa. They noted that the product label already contains a warning about significant and sometimes fatal bleeds, but that the agency is working to determine whether bleeding events are occurring more commonly than would be expected, based on the initial clinical trials supporting the drug's approval.

It wasn't long before the first Pradaxa lawsuits were filed, with plaintiffs alleging serious injuries resulting from Pradaxa bleeding. Early cases were filed in March 2012 in Tennessee, Kentucky, and the Western District of Louisiana.