A combined antithrombotic regimen of rivaroxaban plus aspirin was safe and effective for reducing ischemic events in patients with symptomatic peripheral artery disease who had just undergone peripheral artery revascularization in VOYAGER PAD, a multicenter randomized trial with nearly 6,600 patients.
The study and its results were a groundbreaking advance for this patient population, who until now have had no evidence-based treatment available, Mark P. Bonaca, MD, said on March 28 at the joint scientific sessions of the American College of Cardiology and the World Heart Federation. The meeting was conducted online after its cancellation because of the COVID-19 pandemic.
The study design excluded a small percentage of patients (about 2%) because of their very high bleeding-risk history. Among the treated patients, in those who received a combination of 2.5 mg rivaroxaban twice daily plus 100 mg of aspirin daily, bleeding events were more common, compared with control patients who received aspirin alone. But the patients who received both drugs showed no excess of fatal bleeds or intracranial hemorrhages, and the rate of ischemic events prevented by rivaroxaban plus aspirin exceeded the excess rate of bleeds by three- to sixfold, depending on how bleeding episodes were defined, noted Dr. Bonaca, executive director of CPC Clinical Research and CPC Community Health, an academic research organization affiliated with the University of Colorado at Denver in Aurora.
“This was a much anticipated and important trial. Those of us who treat patients with lower-limb peripheral artery disease have not had much evidence on how to treat these patients, particularly those who have just undergone revascularization. This trial gives us the evidence,” commented Mark A. Creager, MD, professor of medicine and director of the Heart and Vascular Center at Dartmouth-Hitchcock Medical Center in Lebanon, N.H. “The bleeding risk [from adding rivaroxaban treatment] was substantially less than the benefit from preventing major adverse limb events and major adverse cardiovascular events,” producing a “favorable balance” of benefit, compared with risk, Dr. Creager said in an interview. “In the right patients, the benefit greatly outweighed the risk.”
“This was an incredible trial that will advance care,” commented Joshua A. Beckman, MD, professor of medicine and director of Vascular Medicine at Vanderbilt University in Nashville, Tenn. “The treatment was beneficial for patients across a range of symptom severity, from claudication to critical limb ischemia,” and the results expand the range of patients proven to benefit from the rivaroxaban plus aspirin combination from the types of patients with peripheral artery disease (PAD) enrolled in the COMPASS trial.
That pivotal trial showed similar benefit from the dual-antithrombotic regimen, but in patients who had both coronary artery disease as well as atherosclerotic disease in at least one additional vascular bed, such as lower-limb arteries (N Engl J Med. 2017 Oct 5;377:1319-30). In addition to “bringing acute limb ischemia to the cardiovascular community,” the results also identified a very useful time point in the clinical presentation of these patients for starting a combined rivaroxaban plus aspirin regimen: when patients are hospitalized for their revascularization procedure, said Dr. Beckman, a designated discussant for the report.
Among the 6,564 patients randomized in the study, about two-thirds underwent endovascular revascularization within 10 days before starting their study treatment, and the remaining third had undergone surgical revascularization. The study focused on patients “with symptomatic PAD but without known coronary artery disease,” noted Dr. Bonaca.
VOYAGER PAD trial
The VOYAGER PAD (Vascular Outcomes Study of Acetylsalicylic Acid Along With Rivaroxaban in Endovascular Or Surgical Limb Revascularization for Peripheral Artery Disease) trial enrolled patients during 2015-2018 at 534 sites in 34 countries.
The study’s primary endpoint was a composite of acute limb ischemia, major amputation for vascular causes, myocardial infarction, ischemic stroke, or death from cardiovascular causes, and was reduced during a median follow-up of 28 months from 19.9% with aspirin alone to 17.3% on the combined regimen, a 2.6% absolute difference and a 15% relative risk reduction that was statistically significant, an endpoint primarily driven by a reduction in acute limb ischemia.
The primary safety endpoint was the rate of TIMI (Thrombolysis in Myocardial Infarction) major bleeds, which was 0.8% higher in the patients who received the anticoagulant, a 43% relative increase that just missed statistical significance. But that result demonstrated the small but important increased risk for bleeding events that the dual regimen produced in these patients, Dr. Bonaca said.
Simultaneously with his report the findings also appeared in an article published online (N Engl J Med. 2020 Mar 28. doi: 10.1056/NEJMoa2000052).
Dr. Bonaca cautioned that one limitation of his report on the primary outcome of VOYAGER PAD is that the results of an important subgroup analysis won’t be known until a second report during the ACC online sessions on March 29, which will examine the impact that treatment with the antiplatelet drug clopidogrel had on both the efficacy and safety outcomes.
Half of the enrolled patients received clopidogrel at the discretion of their treating physicians; addition or exclusion of concurrent clopidogrel treatment was outside of the study’s design. “Is efficacy the same with or without clopidogrel, and what is the bleeding cost,” especially in patients who receive three antithrombotic drugs? “It will be very important to understand,” Dr. Bonaca said.
“Until now, we had no idea of what was the best antithrombotic strategy for patients after a successful peripheral vascular intervention.” VOYAGER PAD was “an unprecedented vascular study that addressed an unmet patient need,” commented Roxana Mehran, MD, a designated discussant for the study and professor of medicine and director of Interventional Cardiovascular Research at Mount Sinai Medical Center in New York.
VOYAGER PAD was sponsored by Bayer and Janssen, the companies that market rivaroxaban (Xarelto). The institution that Dr. Bonaca directs has received research funding from Bayer and Janssen, and also from Amgen, Aralez, AstraZeneca, Merck, Novo Nordisk, Pfizer, and Sanofi. Dr. Creager had no disclosures. Dr. Beckman has served as a data safety monitor for Bayer and for Novartis, and has been a consultant to Amgen, AstraZeneca, JanOne and Sanofi. Dr. Mehran has received research funding from Bayer and has been a consultant to Janssen, and she has also received research funding or been a consultant to several other companies.
American College of Cardiology 2020 Scientific Session (ACC.20)/World Congress of Cardiology (WCC). Abstract 402.10. Presented March 28, 2020.
N Engl J Med. 2020; Published online March 28, 2020. Full text
This article originally appeared on MDEdge.com.