Antiplatelet Therapy: Rivaroxaban No Riskier than Aspirin

In a second study comparing rivaroxaban (Xarelto/Bayer-Janssen) with aspirin, researchers found rivaroxaban given in addition to an antiplatelet medication did not put patients at increased risk of bleeding.

Reporting this morning at the ACC Scientific Sessions on a study known as GEMINI-ACS-1, E. Magnus Ohman, MD, professor of medicine at Duke University Medical Center said that lifelong aspirin is the usual regimen for patients with acute coronary syndrome.

That is the case “even though there is little evidence that this is effective in preventing a recurrent heart attack after the early phase in ACS,” Ohman said.

“This study is important because it is the first to show that replacing aspirin with a newer, more targeted drug—low-dose rivaroxaban, an anticoagulant—presents no additional risk of bleeding complications when given as dual therapy with an antiplatelet drug,” he said.

Aspirin plus antiplatelet is the recommended treatment, according to current American College of Cardiology/American Heart Association guidelines for care after a heart attack. But some studies have shown that such patients (about 10%) will nevertheless have a second adverse event including heart attack and stroke.

Adding rivaroxaban to dual antiplatelet therapy increases the risk of bleeding complications.

The current study showed with rivaroxaban there was no additional bleeding risk compared to aspirin, a rate of 5.3% with rivaroxaban and 4.9% in patients who got aspirin, a difference that was no significant the research team said.

In the trial, 3,037 patients in 21 countries were enrolled within 10 days of being hospitalized with a heart attack or unstable angina.

After getting stable dose of an antiplatelet (clopidolgrel or ticagrelor) for more than 48 hours, patients got either low-dose rivaroxaban (2.5 mg twice a day) or aspirin (100 mg a day.)

Patients were treated for a median 291 days and the study was double blinded.

Researchers also tracked death rates from cardiovascular causes and blood clots in stented coronary arteries.

They found the rates of these adverse events were about the same in each group, or 5% in the rivaroxaban group and 4.7% in the aspirin group.

At a news conference Ohman was asked if the added cost of rivaroxaban was worth it.

"It's more expensive than aspirin, but this was a phase 2 trial," Ohman said, "We haven't looked at ischemic outcomes which is the true issues and we could potentially get better clinical outcomes--then you would figure out the cost effectiveness."

The trial was a phase 2 study and the researchers said a larger phase 3 is needed to show whether the rivaroxaban/antiplatelet regimen is effective in preventing cardiac events.

The study was published online today in The Lancet.