June 16, 2019
ROADSTER-2 Demonstrates Positive Patient Outcomes With Silk Road's Enroute TCAR Systems
June 15, 2019—Silk Road Medical, Inc. announced positive final results for the company’s ROADSTER-2 postmarketing study evaluating real-world use of the Enroute neuroprotection and stent systems in transcarotid artery revascularization (TCAR) procedures.
Vikram Kashyap, MD, National Coprincipal Investigator of ROADSTER-2, presented the findings at the Society for Vascular Surgery's (SVS) Vascular Annual Meeting held June 12–15 in National Harbor, Maryland.
According to the company, the study demonstrated compelling patient outcomes with low stroke and combined stroke-and-death rates of 0.6% and 0.8%, respectively, in 632 patients at high surgical risk who were enrolled across 42 sites. Notably, 70% of the patients enrolled in the study were from physicians new to TCAR. The ROADSTER-2 data, along with the updated results from the TCAR Surveillance Project, support the case for TCAR as the standard of care in patients at high surgical risk, stated the company.
In Silk Road's announcement, Dr. Kashyap commented, “The results of ROADSTER-2 continue to demonstrate the safety, effectiveness, and clinical advantages of TCAR, especially given that a majority of the TCAR procedures were performed by a broad group of physicians with no previous TCAR experience. The study results highlight the short learning curve of the TCAR procedure and its remarkable consistency and reproducibility and, I believe, will further encourage physicians to broadly adopt the TCAR procedure." Dr. Kashyap is Chief of Vascular Surgery and Endovascular Therapy at University Hospitals Case Medical Center in Cleveland, Ohio.
Designed as a follow-on study to the pivotal ROADSTER trial, ROADSTER-2 is a prospective, multicenter study designed to assess the real-world usage of the Enroute transcarotid stent when used with the Enroute transcarotid neuroprotection system by physicians of varying experience with the TCAR procedure.
The study met its primary endpoint of procedural success, defined as acute device and technical success in the absence of stroke, death, or myocardial infarction (MI) at 30 days, at 97.9%.
TCAR showed low rates of 30-day major adverse events, including:
- 1.7% stroke, death, and MI
- 0.8% stroke and death
- 0.6% stroke (including 0.6% in symptomatic patients, 0.5% in females, and 1.1% in patients aged > 75 years)
In addition, ROADSTER-2 showed lower rates of acute (1.3%) and permanent (0.5%) cranial nerve injury than is typically observed for patients undergoing carotid endarterectomy (CEA).
In an interview with Endovascular Today, Dr. Kashyap addressed the ROADSTER-2 results—specifically, how the 30-day composite endpoint (stroke, death, or MI) of 1.7% was even lower than the 30-day composite endpoint of 3.7% reported in the ROADSTER investigational device exemption trial. He commented to Endovascular Today, “What an amazing story. This is a testament to the ROADSTER-2 investigators who were responsible for this data and to the resilience of the TCAR procedure and technology. ROADSTER-2 had 80% new operators who were ‘TCAR naïve’ before participating in ROADSTER-2. All of them were credentialed in CEA and many were trained in transfemoral carotid artery stenting; so, they had lots of experience in carotid disease, but we were still surprised by these very favorable results.”
In discussing the 42% reduction in contrast usage from ROADSTER to ROADSTER-2, Dr. Kashyap noted that in ROADSTER there was a mandate in the protocol to do intracranial views, both anteroposterior and lateral, which was not the case in ROADSTER-2; this may account for the decrease overall in the contrast usage, along with the use of road mapping and other imaging techniques.
Earlier at the SVS meeting, Mahmoud B. Malas, MD, Principal Investigator of the TCAR Surveillance Project, presented “Outcomes of Transcarotid Revascularization with Dynamic Flow Reversal Versus Carotid Endarterectomy in the Transcarotid Revascularization Surveillance Project.” Dr. Malas reported that there were no statistical differences noted between TCAR and CEA for in-hospital stroke or in-hospital stroke and death.
The text and tables by Malas et al are available online in Journal of Vascular Surgery (2019;69:e95–e96). The TCAR Surveillance Project, a key initiative of the SVS's Vascular Quality Initiative, is an open-ended registry intended to compare real-world patient outcomes between TCAR and CEA.