A new study suggests that the potential for bleeding side effects associated with Xarelto and other new-generation blood thinners may increase if the drugs are used in combination with certain medications, including amiodarone, Rifadin, Diflucan, and Dilantin.
According to a paper published October 3rd in the Journal of American Medical Association (JAMA), researchers from Taiwan analyzed data on 91,000 patients who were using novel anticoagulants, including Xarelto, Eliquis and Pradaxa, either alone or with other medications.
Their findings indicated that patients who took the anti-fungal medication Diflucan in combination with Xarelto or other novel-anticoagulant were the mostly likely to suffer a major bleeding event, with 241.92 incidents per 1,000 person-years.
Taken alone, novel anticoagulants were associated with just 38 incidents per 1,000 person-years.
“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 authors of the study concluded. “Physicians prescribing NOAC medications should consider the potential risks associated with concomitant use of other drugs.”
Xarelto was approved by the U.S. Food & Drug Administration (FDA) in October 2011. As was the case with Pradaxa and Eliquis, it was marketed as an improvement on warfarin, a blood thinner that has been on the market for decades. Among other things, marketing materials for the new medication touted Xarelto’s once-daily dose regimen and promised patients they would not be subjected to a regular blood-testing protocol.
Court documents indicate that more than 18,000 Xarelto lawsuits have been filed in U.S. courts on behalf of patients who allegedly suffered serious internal bleeding events, including cerebral hemorrhage, hemorrhagic stroke, and gastrointestinal bleeds, while taking the medication. All of the complaints question Xarelto’s purported superiority over warfarin, and point out that bleeding associated with the older drug can be stopped via the administration of vitamin K. However, there is currently no approved agent to reverse Xarelto bleeding side effects. Plaintiffs further contend that Xarelto patients would benefit from regular blood monitoring and question the efficacy of its one-size-fits-all, once-daily dosing scheme.
More than 1,500 Xarelto lawsuits have been centralized in a mass tort program in Pennsylvania’s Philadelphia Court of Common Pleas. According to The Legal Intelligencer, the court is currently preparing to convene its first bellwether trial next month, the outcome of which could provide insight into possible jury decisions in similar Xarelto claims. In preparation for that trial, the Court is considering several summary judgment motions filed on behalf of Bayer and Johnson & Johnson, including a motion to bar punitive damages, as well as a motion that seeks to prevent former FDA Commissioner David Kessler from testifying for the plaintiff.
Plaintiffs have also filed several pretrial motions, including one that seeks to bar experts from testifying on the impact of attorney advertising.
The majority of Xarelto lawsuits are pending in a federal multidistrict litigation now underway in the U.S. District Court, Eastern District of Louisiana. Two bellwether trials have already concluded in that proceeding, both of which produced defense verdicts.