NEW ORLEANS—Results of the PIONEER AF-PCI trial suggest certain patients may have a lower risk of bleeding if they receive rivaroxaban rather than a vitamin K antagonist (VKA).
The study showed that patients with nonvalvular atrial fibrillation (NVAF) who underwent percutaneous coronary intervention (PCI) with stenting had a lower risk of clinically significant bleeding if they received rivaroxaban plus antiplatelet therapy rather than a VKA plus antiplatelet therapy.
However, the trial showed no significant difference between the treatment groups when it came to the risk of cardiovascular events.
These results were presented at the American Heart Association’s Scientific Sessions 2016 and simultaneously published in NEJM.
The trial was supported by Janssen Scientific Affairs LLC, and Bayer Health Care Pharmaceuticals.
“In managing the stented patient with atrial fibrillation, a pharmacologic strategy must carefully balance the risk of stent thrombosis, or blood clot, with the risk of bleeding complications,” said study investigator C. Michael Gibson, MD, of Beth Israel Deaconess Medical Center in Boston, Massachusetts.
“This trial, which tested 2 entirely new strategies, now provides us with randomized clinical trial data demonstrating that a combination of rivaroxaban with antiplatelet therapy is successful in minimizing bleeding while preventing clotting.”
The trial included 2124 patients with NVAF who had undergone PCI with stenting. They were randomized to receive, in a 1:1:1 ratio:
- Low-dose rivaroxaban (15 mg once daily) plus a P2Y12 inhibitor for 12 months (group 1)
- Very-low-dose rivaroxaban (2.5 mg twice daily) plus dual antiplatelet therapy (DAPT) for 1, 6, or 12 months (group 2)
- Standard therapy with a dose-adjusted VKA (once daily) plus DAPT for 1, 6, or 12 months (group 3).
Key endpoints
The study’s primary safety endpoint was clinically significant bleeding, which was a composite of major bleeding according to Thrombolysis in Myocardial Infarction (TIMI) criteria, minor bleeding according to TIMI criteria, and bleeding requiring medical attention.
At 1 year, the rate of clinically significant bleeding was significantly lower in the 2 rivaroxaban groups than in the VKA group—16.8% in group 1, 18.0% in group 2, and 26.7% in group 3.
The hazard ratio for group 1 compared to group 3 was 0.59 (P<0.001). And the hazard ratio for group 2 compared to group 3 was 0.63 (P<0.001).
The researchers said this reduction in bleeding for the 2 rivaroxaban groups was consistent across multiple subgroups of patients.
The study’s key efficacy endpoint was major adverse cardiovascular events, which was a composite of death from cardiovascular causes, myocardial infarction, and stroke.
There was no significant difference between the groups with regard to this endpoint. It occurred in 6.5% of the patients in group 1, 5.6% in group 2, and 6.0% in group 3 (P>0.05 for both comparisons).
“For the first time in this population, a treatment regimen resulted in less bleeding than the current standard of care,” Dr Gibson said.
“Pairing rivaroxaban with single or dual antiplatelet therapy has the potential to transform current practice, as demonstrated in this study, with significantly less bleeding and numerically similar efficacy when compared to warfarin [VKA] with dual antiplatelet therapy.”
