Xarelto, Eliquis and Pradaxa Bleeding Risks Increase When Taken With Some Drugs: Study

Amid continuing concerns about the safety of a new crop of anticoagulants released in recent years, the findings of new research suggest that the bleeding risks linked to Xarelto, Pradaxa and Eliquis could be increased when the new-generation blood thinners are taken together with certain drugs, such as amiodarone, Rifadin, Diflucan, and Dilantin. 

In a study published in the Journal of the American Medical Association (JAMA) on October 3, researchers warn that doctors need to look closer at the potential bleeding risks of non-vitamin K oral anticoagulants (NOACs) when patients are taking other drugs.

Xarelto (rivaroxoaban), Eliquis (apixaban) and Praxaxa (dabigatran) were introduced in recent years as superior alternatives to warfarin, which has been the go-to anticoagulation treatment to prevent blood clots for decades.

While the drugs have been aggressively promoted as easier to use, claiming that they do not require the same close monitoring to maintain appropriate dose, concerns have emerged about the bleeding risks, as thousands of reports suggest that users may experience severe and uncontrollable bleeding problems, since the drugs did not have an approved reversal agent at the time they were introduced.

Unlike warfarin, where the blood thinning effects of the drug can be reversed quickly with vitamin K and fresh frozen plasma if bleeding problems develop, no safe and effective antidote was available for Xarelto, Eliquis or Pradaxa when they were introduced.

In this new study, researchers from Taiwan looked at data on more than 91,000 users of the new oral anticoagulants, who took the drugs either alone or with concurrent medications.

According to the findings, the risks of major bleeding increased when patients took one of the blood thinners as well as amiodarone, Rifadin (rifampin), Diflucan (fluconazole), and Dilantin (phenytoin) at the same time. Diflucan, an antifungal medication, was linked with the highest major bleeding risk, with 241.92 major bleeding incidents per 1,000 person-years. That compared to about 38 incidents per 1,000 person-years for those taking Xarelto, Pradaxa or Eliquis alone. The other drugs that increased bleeding risks did not come anywhere close, with less than half those incidents at most.

“Among patients taking NOACs for nonvalvular atrial fibrillation, concurrent use of amiodarone, fluconazole, rifampin, and phenytoin compared with the use of NOACs alone, was associated with increased risk of major bleeding,” the researchers concluded. “Physicians prescribing NOAC medications should consider the potential risks associated with concomitant use of other drugs.”

Uncontrollable Bleeding Lawsuits

The findings come as more than 18,000 Xarelto lawsuits continue to move forward through the federal court system against Bayer Healthcare and Janssen Pharmaceuticals, alleging that users suffered severe and uncontrollable bleeding events on the drug. Each of the complaints allege that the drug makers failed to provide adequate warnings and instructions for physicians.

Similar allegations were raised in thousands of Pradaxa lawsuits filed several years ago, as that other new-generation anticoagulant hit the market before Xarelto. However, the maker of that competing drug ultimately agreed to pay $650 million in Pradaxa settlements just before the first bellwether trials were set to begin, with an average of about $150,000 per claim.

Given the similar questions of fact and law raised in the Xarelto cases, all lawsuits are centralized before U.S. District Judge Eldon Fallon in the Eastern District of Louisiana, as part of an MDL or multidistrict litigation, where a series of early trial dates are being held to help gauge how juries may respond to certain evidence and testimony that is likely to be repeated throughout the claims. While the outcomes of these “bellwether” trials are not binding on other plaintiffs, they are being closely watched and may influence eventual Xarelto settlements that would avoid the need for thousands of individual cases to go to trial nationwide.