The absolute benefit of adding low-dose rivaroxaban to low-dose aspirin following revascularization for symptomatic lower-extremity peripheral artery disease (PAD) is significantly greater in patients with comorbid coronary artery disease (CAD), according to a new secondary analysis of the VOYAGER PAD trial.
“These findings suggest heterogeneity of prognostic risk for ischemic events in lower-extremity PAD patients, and may support shared decision-making with these patients,” William R. Hiatt, MD, observed in presenting the study results at the virtual annual congress of the European Society of Cardiology.
VOYAGER PAD was a 3-year, 34-country clinical trial in which 6,564 patients with symptomatic PAD who had recently undergone lower-limb revascularization were randomized in double-blind fashion to rivaroxaban (Xarelto) at 2.5 mg twice daily or placebo on top of background standard therapy with low-dose aspirin.
Among the 2,067 participants with baseline comorbid CAD, the primary outcome – a composite comprised of cardiovascular death, acute MI, ischemic stroke, acute limb ischemia, and major amputation – occurred in 18.9% of the rivaroxaban group at 3 years and 24.3% on placebo, for a highly significant 22% relative risk reduction.
In contrast, in the 4,497 patients with PAD only, the primary outcome occurred in 16.1% of those on rivaroxaban and 17.9% of controls, an 11% relative risk reduction which failed to reach statistical significance. The absolute risk reduction achieved with rivaroxaban was 5.4% in patients with PAD plus CAD versus 1.8% in those with PAD alone. Thus, the significant clinical benefit with rivaroxaban plus aspirin previously reported in the overall study population, with a number needed to treat for 3 years of 39 in order to prevent one primary outcome event, was largely driven by the superior outcomes in the dual-diagnosis subgroup, reported Dr. Hiatt, professor of medicine at the University of Colorado at Denver, Aurora.
“A strategy of rivaroxaban at 2.5 mg twice daily plus low-dose aspirin versus low-dose aspirin alone reduces ischemic events of the limb, brain, and heart, but also increases bleeding, with an overall net benefit,” the cardiologist said. “In particular, the benefits of this strategy for MI and ischemic stroke are robust, especially in patients with PAD and CAD.”
Indeed, the MI rate at 3 years in the dual diagnosis subgroup was 7.3% with rivaroxaban and 8.8% with placebo, for a 23% relative risk reduction, compared with rates of 3.3% and 3.7%, respectively, in patients with PAD only. Similarly, ischemic stroke occurred in 2.9% of patients with PAD and CAD in the rivaroxaban group, compared with 3.9% with placebo, whereas the rate in the PAD only group was identical at 2.6% regardless of whether patients were on rivaroxaban or placebo.
In patients without CAD, the clinical benefit of rivaroxaban was driven by reductions in severe limb events. Their rate of acute limb ischemia was 5.2% with rivaroxaban, compared with 8.3% with placebo, for a 37% relative risk reduction. In contrast, the reduction in acute limb ischemia with rivaroxaban in patients with PAD and CAD wasn’t significantly different from placebo.
Thrombolysis in Myocardial Infarction major bleeding occurred in 2.4% of patients with PAD and CAD on rivaroxaban, compared with 1.1% on placebo, and in 1.7% and 1.5% of patients with PAD alone. Of note, rates of ischemic stroke or fatal hemorrhage were low and similar at less than 1% in all four groups, Dr. Hiatt noted.
VOYAGER PAD was sponsored by Bayer and Janssen. Dr. Hiatt reported receiving research grant support from those two companies as well as Amgen.