ROADSTER 30-Day Data Published for Silk Road Medical’s Enroute Transcarotid NPS
November 11, 2015—The 30-day safety and efficacy results from the pivotal ROADSTER trial, which were presented last year during a Late-Breaking Clinical Trials Session at the Vascular Interventional Advances (VIVA) meeting held on November 4–7, 2014, in Las Vegas, Nevada, were published by Christopher J. Kwolek, MD, et al in the Journal of Vascular Surgery (2015;62:1227–1234).
ROADSTER is a study of Silk Road Medical Inc.’s Enroute transcarotid neuroprotection system (NPS), which provides direct surgical common carotid access and cerebral embolic protection via high-rate flow reversal during carotid artery stenting (CAS).
Silk Road announced US Food and Drug Administration (FDA) 510(k) clearance for the Enroute transcarotid NPS in February 2015, based in part on the results of the ROADSTER trial. In May, the company announced FDA approval for the Enroute transcarotid stent system.
ROADSTER is a prospective, single-arm, multicenter trial that included patients considered to be at high risk for complications from carotid endarterectomy. Symptomatic patients with ≥ 50% stenosis and asymptomatic patients with ≥ 70% stenosis were eligible to be treated with any FDA-approved carotid artery stent.
As summarized in JVS, the primary endpoint was the composite of all stroke, myocardial infarction (MI), and death at 30 days postprocedure as defined in the FDA-approved study protocol. Secondary endpoints included cranial nerve injury; 30-day stroke, death, stroke/death, and MI; acute device, technical, and procedural success; and access site complications. An independent clinical events committee adjudicated all major adverse events.
The ROADSTER investigators enrolled 208 patients at 18 sites between November 2012 and July 2014. Of these patients, 67 were enrolled as lead-in cases, and 141 patients were enrolled in the pivotal phase.
In the pivotal cohort, 26% of patients were symptomatic and 75% were asymptomatic. Acute device and technical success were 99% (140 of 141). By hierarchical analysis, the all-stroke rate in the pivotal group was 1.4% (2 of 141); the stroke and death rate was 2.8% (4 of 141); and the rate of stroke, death, and MI was 3.5% (5 of 141). One patient (0.7%) experienced postoperative hoarseness from potential tenth cranial nerve injury, which completely resolved at the 6-month follow-up visit.
The investigators concluded that results from ROADSTER demonstrate that the use of the Enroute transcarotid NPS is safe and effective at preventing stroke during CAS. The overall stroke rate of 1.4% is the lowest reported to date for any prospective, multicenter clinical trial of CAS, advised the investigators in JVS.