SEER Meta-Analysis Supports Medtronic’s Solitaire Stent Retriever For Acute Ischemic Stroke Treatment
February 23, 2016—Medtronic plc announced that results from the Safety and Efficacy of Solitaire Stent Thrombectomy (SEER)—Individual Patient Data Meta-Analysis of Randomized Trials were presented at the International Stroke Conference, which was held February 17 to 19 in Los Angeles, California. Investigators found that the addition of the company’s Solitaire stent retriever to the current pharmaceutical treatment—intravenous tissue plasminogen activator (IV-tPA)—significantly improves functional outcomes in patients experiencing stroke.
SEER also showed a significant reduction (20% vs 40%; adjusted odds ratio, 3.7 (1.3–10.6); P = .01) in mortality for patients over the age of 80 years. Bruce C.V. Campbell, MBBS, et al published the SEER findings simultaneously in Stroke (2016;47:798–806).
SEER assessed four global clinical trials published last year in the New England Journal of Medicine (NEJM). SEER is the first patient-level global meta-analysis of the four randomized trials and the first to examine data from a total of 787 patients. The trials are:
- SWIFT PRIME (Solitaire FR With the Intention For Thrombectomy as Primary Endovascular Treatment for Acute Ischemic Stroke) published by Jeffrey L. Saver, MD, et al in NEJM (2015;372:2285–2295);
- REVASCAT (Endovascular Revascularization With Solitaire Device Versus Best Medical Therapy in Anterior Circulation Stroke Within 8 Hours) published by Tudor G. Jovin, MD, et al in NEJM (2015;372:2296–2306);
- EXTEND-IA (Extending the Time for Thrombolysis in Emergency Neurological Deficits—Intra-Arterial) published by Dr. Campbell et al in NEJM (2015; 372:1009–1018);
- ESCAPE (Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke) published by Mayank Goyal, MD, et al in NEJM (2015;372:1019–1030).
According to Medtronic, the analysis showed that patients experiencing an acute ischemic stroke and who were treated with the Solitaire stent retriever, when eligible, had significantly improved independent functional outcomes (mRS, 0–2) at 90 days than patients treated with IV-tPA alone (54% vs 31.5%; P < .0001).
The analysis also found that patients over the age of 80 years and in good health had a clinically and statistically significant 20% absolute reduction in mortality. Further, the analysis showed a strong significance in the numbers needed to treat (2.5) and reduce disability (ie, for every 2.5 patients treated with the Solitaire device plus IV-tPA, one patient showed improved functional outcomes).
The company noted that the study showed a time-benefit relationship for treatment of patients with acute ischemic stroke, with a decline in the probability of independent functional outcome with longer time from symptom onset to reperfusion.
In Medtronic’s press release, Dr. Campbell commented, “The SEER analysis confirms the overall benefits of the Solitaire stent retriever device and provides important insights into clinical subgroups where the benefits were not clear cut in the individual trials. The meta-analysis showed that patients over the age of 80 clearly benefited with significantly reduced mortality. Patients with contraindications to IV-tPA, as well as those with more challenging blocked arteries in both the neck and brain, also show a clear benefit from Solitaire.”
Dr. Goyal added, “Treatment with the Solitaire stent retriever was very successful with extremely low complication rates and low symptomatic intracranial hemorrhage. The pooled data represent a broad sample of health care systems, countries, and hospitals and demonstrates applicability in different health systems around the world.”
In June 2015, the American Heart Association/American Stroke Association announced the publication of new stroke treatment guidelines that recommended the use of stent retriever technology, such as the Solitaire stent retriever device, in conjunction with IV-tPA as a first-line treatment for eligible patients, noted Medtronic.
The February 2016 issue of Endovascular Today, under the guest medical editorship of Donald Frei, MD, is dedicated to ischemic stroke intervention and provides an in-depth look at the paradigm shift in managing emergent large vessel occlusion. In the issue, Frank J. Attenello, MD, and William J. Mack, MD, provide an overview of the key trials to date. Dr. Frei noted that although milestone conclusions were arrived upon in these trials, new questions were also brought to light, the answers to which will shape the further improvement of treatment capabilities. Additionally, Reade A. De Leacy, MBBS, and J. Mocco, MD, explore some of these key areas in an article discussing what types of trials are needed, as well as those that are currently underway.