Proposed Reversal Agent Works For Major Xarelto, Eliquis Bleeding Events: Study

The findings of new research suggest that a proposed reversal agent, which is designed to allow doctors to quickly stop bleeding problems with Xarelto, Eliquis and similar blood thinners, would be effective and potentially life-saving if it is approved by U.S. regulators. 

In a study published late last month in the New England Journal of Medicine, researchers found that a two hour infusion of andexant alfa substantially reduced the blood thinning effects associated with a new class of anticoagulants, known as Factor Xa inhibitors, which have been linked to problems with uncontrollable bleeding due to the lack of an antidote.

The proposed reversal agent is designed to allow doctors to control and stop major bleeding associated with Xarelto and Eliquis, which have become increasingly popular alternatives to warfarin in recent years, as they are marketed as easier to use. However, unlike warfarin, for which the blood thinning effects can be quickly reversed, no safe and effective antidote for Factor Xa inhibitors was available at the time the drugs were introduced.

Since the drugs have hit the market, thousands of reports involving uncontrollable Xarelto bleeding problems have plagued the new drugs, and there are currently more than 7,000 Xarelto injury lawsuits filed nationwide, alleging that the Bayer Healthcare and Janssen Pharmaceuticals sold an unreasonably dangerous and defective anticoagulant, without warning about the lack of an available reversal agent.

In this new study, researchers evaluated 67 patients who suffered from acute major bleeding within 18 hours of being given a dose of a Factor Xa inhibitor. According to the findings, the effects of the drugs decreased by 89% in patients treated with Xarelto, and by 93% in patients treated with Eliquis. Twelve hours after being given the dose, bleeding events decreased to levels graded good or excellent in 37 out of 47 patients given Andexanet Alfa, the researchers found.

The proposed drug, given the brand name AndexXa, was developed by Portola Pharmaceuticals, and has been submitted to the FDA for approval. However, last month the FDA indicated that it requires additional information regarding the manufacturing of the drug, and data on whether the drug can be used with the blood thinners Savaysa and Lovenox, before it can be approved.

The FDA did approve Praxbind in October 2015, which is a reversal agent for the Factor Xa inhibitor Pradaxa, which was the first member of this class to hit the market. However, Portola sought approval to market AndexXa as a reversal agent for Xarelto and Eliquis, which were the second and third members of this class, respectively.

The approval of a reversal agent for Xarelto and Eliquis has been sought by the drug makers, since it is widely acknowledged that this will make the drugs substantially safer.

According to allegations raised in product liability lawsuits filed against the drug makers, the new generation anticoagulants never should have introduced before a safe and effective reversal agent was available, seeking damages for severe bleeds and wrongful deaths caused by problems on Xarelto and Eliquis.

A series of Xarelto bellwether trials are expected to begin early next year in the federal court system, which are designed to help parties gauge how juries may respond to certain evidence and testimony that is likely to be repeated throughout the litigation.

Thousands of Pradaxa lawsuits were filed against the makers of that competitor drug before the introduction of Praxbind, and the drug makers ultimately agreed to pay $650 million to settle about 4,000 cases.

It is widely expected that Xarelto settlements will require a substantially larger payment, given the larger market share and wider spread reports of problems among users of the controversial anticoagulant.