Xarelto, Similar Blood Thinners, Have Same Rate of Bleeding Events As Warfarin: Study

The findings of two new studies suggest that newer blood thinners, such as Xarelto and Pradaxa, carry about the same bleeding risk as the much older drug they are trying to replace, warfarin. 

Canadian researchers published a study in The BMJ on October 17, which indicates that use of the new generation blood thinners for patients with atrial fibrillation carries similar bleeding risks as warfarin, a drug several decades older.

The study looked at data on nearly 60,000 adults, including about 12,500 who used newer blood thinners and more than 47,000 who used warfarin for treatment of blood clots.

The findings indicate that the risk of major bleeding events were virtually the same, with about 3.3% suffering major bleeding and 1.7% dying from bleeding events and all cause mortality within 90 days of treatment. The new drugs did not increase nor decrease bleeding risks, according to the study

The findings are similar to another recent study, which sought to establish that Xarelto was safer and more effective than the blood thinner warfarin, but instead found that there is little safety difference between the two drugs when looking at the risk of stroke and brain hemorrhage.

That research was conducted by scientist from South Korea, and was published in JAMA Neurology on September 11. According to the findings, neither drug outperformed the other in efficacy or prevention ischemic strokes linked to atrial fibrillation.

In the Korean study, researchers conducted a randomized clinical trial involving 195 patients in South Korea from April 28, 2014 to December 7, 2015 at 14 academic medical centers. Half of the patients were given Xarelto (rivaroxoaban) and half were placed on warfarin treatment.

According to the findings, 49.5% of patients suffered Xarelto side effects that included ischemic stroke, new ischemic lesions or new intracranial hemorrhage after four weeks. That compares to 54.5% of patients with warfarin, which the researchers determined was a nonsignificant difference.

“Rivaroxaban and warfarin had comparable safety and efficacy for early anticoagulation in mild atrial fibrillation–related acute ischemic stroke,” the researchers determined. “In atrial fibrillation (AF)–related acute ischemic stroke, the optimal oral anticoagulation strategy remains unclear.”

Xarelto Bleeding Concerns

For the last several years, the safety of Xarelto and other new-generation blood thinners has been heavily debated, as the drugs have been linked to a number of adverse event reports involving uncontrollable bleeding.

Xarelto is part of a new generation of novel oral anticoagulants and was introduced in 2011, as a superior alternative to warfarin, which has been the go-to anti-clotting treatment for decades. However, more than 18,000 Xarelto lawsuits have been filed against Bayer Healthcare and Janssen Pharmaceuticals, indicating that the drug makers provided inadequate warnings and precautions for users and the medical community.

While all blood thinners may cause bleeding, the side effects of warfarin can be quickly reversed with a widely known antidote. However, there was no Xarelto reversal agent when the drug was introduced, and plaintiffs allege that Bayer and Johnson & Johnson withheld information about the lack of an antidote, and failed to recommend necessary monitoring to reduce the risk of uncontrollable bleeds.

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.

As Xarelto bleeding lawyers continue to review potential cases for individuals prescribed the anticoagulant throughout the United States, the number of complaints has surpassed the number of claims involved in the Pradaxa litigation, as the drug has become more widely used in recent years.