Secondary analysis backs safety of apixaban over warfarin

A secondary analysis of the AUGUSTUS trial confirms earlier findings that treating heart patients with the anticoagulant apixaban results in less major bleeding, hospitalization and death than warfarin, a standard-of-care blood thinner.

The latest review of AUGUSTUS was headed by Maria Cecilia Bahit, MD, and presented at the American Stroke Association’s International Stroke Conference in Los Angeles on Feb. 21. Cecilia Bahit, the chief of cardiology at INECO Neurociencias in Rosario, Santa Fe, Argentina, and her team split up the original AUGUSTUS patient population to more closely study individuals’ outcomes.

“We divided the AUGUSTUS study population into two groups: patients with prior stroke/transient ischemic attack/thromboembolism and those with no prior stroke/transient ischemic attack/thromboembolism,” Cecilia Bahit said in a release.

When AUGUSTUS results were first reported at the American College of Cardiology’s annual scientific sessions in New Orleans last March, the study’s authors revealed that treatment with apixaban was safer than treatment with a vitamin K antagonist like warfarin in certain CV patients. The trial recruited 4,614 individuals with either AFib and acute coronary syndrome or percutaneous coronary intervention plus planned treatment with a P2Y12 inhibitor and randomized them to apixaban or a vitamin K antagonist. Patients also received aspirin or a matching placebo for six months.

AUGUSTUS investigators reported that, six months into the study, 10.5% of patients receiving apixaban experienced a clinically relevant bleeding event, compared to 14.7% of patients on warfarin.

Looking at the efficacy and safety of apixaban versus warfarin a year later, Cecilia Bahit et al. found that taking apixaban without aspirin was linked to the lowest rates of bleeding, death and hospitalization, regardless of a patient’s history of prior stroke. People who presented with a history of stroke were automatically at an increased risk of ischemic bleeding, hospitalization and death compared to their peers with no history of stroke.

Cecilia Bahit and colleagues said their analysis supports the idea that the risk of bleeding is greater with aspirin than with placebo for patients with no prior CV events. The highest rate of bleeding was observed in individuals who received both warfarin and aspirin, and there was no significant difference between aspirin and placebo for other clinical outcomes.

“These results reinforce the main results of the AUGUSTUS trial by assuring physicians that even in a high-risk group of patients with prior stroke, ‘less is more,’” Cecilia Bahit said. “In other words, a strategy of apixaban plus a P2Y12 inhibitor without aspirin has the most favorable outcomes, and triple therapy—a vitamin K antagonist plus aspirin plus a P2Y12 inhibitor—should be avoided.”