The Solitare stent retriever Medtronic (NYSE:MDT) acquired for $50 billion last year when it bought Covidien is safe and highly effective when combined with standard care using the thrombolysis drug alteplase, according to a meta-analysis of 4 previous trials of the device.
The transcatheter Solitaire device uses a stent-like device to trap and retrieve a blood clot in the brain in cases of ischemic stroke. Researchers from the 4 trials – Swift Prime, Revascat, Extend-IA and Escape – pooled their data to examine the results from 787 patients, randomized to either thrombectomy with the Solitaire device (401) or standard care using just the drug (386). About 82% of the total patient population received intravenous thrombolysis, according to the study, which was published today in the journal Stroke and presented at the International Stroke Conference in Los Angeles.
The primary outcome for the Seer study was scores on the Modified Rankin Scale, a commonly used outcome measure in stroke trials that ranks symptoms using a scores ranging from 0 (no symptoms) to 5 (severe disability; bedridden, incontinent and requiring constant nursing care and attention) and 6 (dead). The Seer study excluded patients in whom Solitaire was not the 1st device used; secondary outcomes included functional independence (Rankin score of 0 to 2); symptomatic intra-cerebral hemorrhage and mortality.
After 90 days, the researchers found, patients treated with the Solitaire device showed a “substantial” benefit, with 40% showing reduced disability, including 23 who reached independence outcomes (a Rankin score of 2 or less). The benefit extended across a broad range of patients, they found, with no major safety concerns and no increase in symptomatic hemorrhage or mortality.
“This analysis confirms the robust treatment benefits of endovascular stent thrombectomy using the Solitaire device in patients with large vessel occlusion ischemic stroke, selected by imaging and treated rapidly within 6 hours of stroke onset. No clinical effect modifiers were identified, indicating that age and stroke severity (within the range included in the trials) should not exclude patients from therapy. Effects in later time windows and in patients with more extensive irreversible brain injury at baseline require further study,” they wrote.
“This analysis confirms the robust treatment benefits of stent retrievers, specifically, the most studied of these devices: The Solitaire stent retriever, across multiple health care systems across the world,” Medtronic global medical affairs senior director Manish Gupta said in prepared remarks. “Medtronic has a longstanding commitment to proving the value of our innovations through scientific research and it is rewarding to see how our data is helping to spark a revolution in stroke care globally.”
“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,” added lead author Bruce Campbell of Australia’s University of Melbourne. “The meta-analysis showed that patients over the age of 80 clearly benefited with significantly reduced mortality. Patients with contraindications to [intravenous alteplase], as well as those with more challenging blocked arteries in both the neck and brain, also show a clear benefit from Solitaire.”