Bayer HealthCare and Janssen Pharmaceuticals recently announced results from the Venture-AF trial that investigated its oral anticoagulant Xarelto.

The trial looked at Xarelto (rivaroxaban) as an alternative to dose-adjusted Vitamin K Antagonists (VKA), such as warfarin, to reduce the risk of blood clots in patients with atrial fibrillation undergoing catheter ablation, a frequently used procedure to remove abnormal tissue in the heart that is causing the irregular heartbeat.

The results were presented at Heart Rhythm 2015, the Heart Rhythm Society’s 36th Annual Scientific Sessions, and published in the European Heart Journal.

Over the past decade, the number of catheter ablation procedures has risen dramatically in the United States, with more than 93,000 procedures performed from 2000-2010. Current guidelines recommend a blood thinner, such as Xarelto, before, during and after the procedure to help prevent blood clots.

The Xarelto Venture-AF study is the first trial of any novel anticoagulant in this high-risk patient population.

Xarelto and Venture-AF

The exploratory trial, known as Venture-AF, was a 248-patient, Phase 3b trial. Patients were recruited from 37 centers in five countries worldwide.  The majority of internal bleeding that occurred in the study was mild or insignificant.

Patients with AF scheduled for catheter ablation, for restoring normal heart rhythm, were randomly given Xarelto 20 milligrams orally once-daily or dose-adjusted VKA.

In patients treated with Xarelto, there were no blood clots or thromboembolic events, while in those patients receiving a VKA, one vascular death and one ischaemic stroke occurred. The company said there was one major thrombosis bleeding event in the VKA treatment arm versus none in the Xarelto treatment group. There were no major bleeding events in either group using TIMI (thrombolysis in myocardial infarction) and GUSTO-defined scales (Global Utilization off Streptokinase and Tpa for Occluded Arteries).

According to researchers, the Venture-AF study results provide physicians with additional insights that may help them manage atrial fibrillation patients who are scheduled for catheter ablation.

Lead researcher, Dr. Andrea Natale, Executive Medical Director, Texas Cardiac Arrhythmia Institute at St. David’s Medical Center in Austin, Texas, stated, “Given the dose adjustments often needed for patients on Vitamin K antagonists, such as warfarin, to ensure the medicine is working effectively, rivaroxaban [Xarelto] may offer a simpler approach in this setting.”

Xarelto Bleeding Risks

Approved in 2011, Xarelto (rivaroxaban) is one of the newest blood thinners on the market. However, there were thousands of serious adverse events, hundreds of which were Xarelto internal bleeding events. While blood thinners are dangerous in general, Xarelto topped the list released by the Institute for Safe Medication Practices (ISMP) as the most dangerous.

The drug is also on its list of high-alert medications, meaning it has a “heightened risk of causing significant patient harm” when used in error. According to Xarelto lawsuits, hundreds of patients died because of bleeding caused by the drug.

In 2012, the FDA reported that three times more people died from adverse events while on Xarelto compared to warfarin. In addition, while it is supposed to prevent blood clots, the federal agency has already received reports of dangerous blood clots in people taking the drug.

The most dangerous side effect for people who take Xarelto is uncontrollable bleeding. The drug does not have an antidote, and in Xarelto lawsuits filed by people who say they were injured by the drug, former Xarelto users say they were not warned sufficiently about the medication’s risk.