Xarelto Antidote Andexanet Alfa Could Gain FDA Approval Soon

andexanet alfa

According to the American Heart Association, 92.1 million Americans live with some form of cardiovascular disease. Many of them rely on prescription blood thinners to control their disease symptoms. For years, doctors preferred warfarin for preventing blood clots, strokes and heart attacks. But recently, newer oral blood thinners called Factor Xa inhibitors began stealing warfarin’s patients. While these drugs, including best-selling Xarelto (generic: rivaroxaban), have some benefits over warfarin, they also carry additional health risks. Perhaps most alarming is the fact that Xarelto has no antidote, leaving patients vulnerable to uncontrolled bleeding episodes. As a result, Portola Pharmaceuticals, Inc. started developing its Xarelto antidote, andexanet alfa (brand name: AndexXa). After fast-tracking AndexXa, the U.S. Food and Drug Administration refused to approve andexanet alfa in August 2016.

Portola Resubmits Andexanet Alfa for FDA Review

Before rushing to judgment, first, let’s look at why the FDA refused to clear andexanet alfa for the U.S. market in 2016. The FDA specifically stated that Portola’s initial application didn’t include sufficient data about how the company manufactures andexanet alfa. In addition, the agency wanted data regarding AndexXa’s efficacy as a reversal agent for other Factor Xa inhibitors besides Xarelto. After that initial denial, Portola regrouped and put in another application for the FDA to review (and hopefully, approve) andexanet alfa in August 2017.

The newer, resubmitted biologics application (BLA) that Portola submitted to the FDA includes all Factor Xa inhibitors, not just Xarelto. Now that the resubmission’s under FDA review, the agency expects to make a decision regarding approval on February 2, 2018.

Why FDA Approval for Andexanet Alfa Matters

To date, Portola is the only pharmaceutical company that’s developed a potential Xarelto reversal agent for the market. That’s why Portola desperately wants FDA approval for andexanet alfa: With zero market competition, AndexXa could be a pharmaceutical game-changer. Since day one, Xarelto patients put themselves at risk for life-threatening or uncontrollable bleeding, which could result in their deaths. While Vitamin K easily reverses warfarin’s effects (or doctors could infuse patients with fresh frozen plasma), Xarelto has no antidote. Portola aims to change that with AndexXa, which is also currently under review for market distribution in the EU.

Portola’s ongoing ANNEXA-4 study evaluates AndexXa’s safety and efficacy as a reversal agent for anticoagulant patients taking Factor Xa inhibitors. In fact, the company recently published a preliminary data analysis in September 2016. The study observed 67 Xarelto patients, 47 of whom were eligible for inclusion and analysis. All participants experienced acute major bleeding within 18 hours after taking Factor Xa inhibitors, including apixaban, rivaroxaban, edoxaban or enoxaparin. At the 18-hour mark, doctors dosed all study subjects with andexanet alfa in hopes of reversing their acute bleeding episodes. After analyzing the drug’s effects, researchers found that andexanet alfa “promptly and significantly” reversed anticoagulant activity by 89%.

Portola’s statement about the study’s results asserted: “Considering the substantial clinical burden of bleeding associated with use of FXa inhibitors, the lack of clinical data to support existing management strategies… and the fact that none of the currently used agents reverse anti-FXa activity, effective bleeding management for patients taking FXa inhibitors remains an unmet clinical need.” Millions of Xarelto patients are waiting to hear whether the FDA will approve AndexXa for the U.S. market in 2018.

Had Serious or Uncontrolled Bleeding With Xarelto?

If you or a loved one suffered life-threatening Xarelto side effects, you’re not alone. Without an approved Xarelto antidote, millions of patients already suffered uncontrolled internal and intracranial bleeding. To see if you may qualify for a cash settlement from Xarelto’s manufacturer, fill out your free claim review now. Once you’ve submitted your information, an advocate will call to discuss how to get the justice and compensation you deserve.