ESCAPE and EXTEND-IA Trials Confirm Benefits of Medtronic's Solitaire Flow Restoration Device for Stroke

February 11, 2015—Medtronic, plc announced that two studies presented at the International Stroke Conference in Nashville, Tennessee, and published online in The New England Journal of Medicine found that stent thrombectomy using the company’s Solitaire device added to the current standard of pharmaceutical treatment with intravenous tissue plasminogen activator (IV-tPA) significantly reduced disability in patients experiencing a stroke. 

Both the ESCAPE (Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke) and the EXTEND-IA (Extending the Time for Thrombolysis in Emergency Neurological Deficits—Intra-Arterial) trials were investigator-initiated trials supported by an unrestricted grant from Medtronic that primarily assessed the addition of the company’s Solitaire device in conjunction with IV-tPA. The grants were originally provided by Covidien, the developer of the Solitaire device. Covidien merged with Medtronic in January 2015.

The company stated that ESCAPE and EXTEND-IA demonstrate the effects of the Solitaire device in restoring blood flow to the brain, reducing stroke morbidity and disability, and reducing the time patients spend in the hospital or rehabilitation center. Both studies met the safety endpoint. 

Jeffrey L. Saver, MD, commented in Medtronic’s press release, “Solitaire stent thrombectomy is the real deal. It represents a sea change in our treatment of acute ischemic stroke.” Dr. Saver is Professor of Neurology at Geffen School of Medicine at UCLA and Director of the UCLA Comprehensive Stroke Center in Los Angeles, California.

The ESCAPE trial was led by Principal Investigator Michael D. Hill, MD, with Study Directors Andrew M. Demchuk, MD, and Mayank Goyal, MD, at the University of Calgary in Alberta, Canada. ESCAPE was sponsored by the University of Calgary in collaboration with Medtronic, the Heart and Stroke Foundation of Canada, and the Hotchkiss Brain Institute of the University of Calgary. Mayank Goyal, MD, et al published the ESCAPE results online ahead of print in the The New England Journal of Medicine.

According to Medtronic, ESCAPE assessed 316 patients and found that patients in the treatment arm had a higher rate of return to functional independence (or reduction in stroke morbidity/disability) and lower risk of death from stroke compared to treatment with IV-tPA alone. Functional independence was statistically significantly improved (53% vs 29%) with 53% of patients returned to functional independence after treatment. ESCAPE showed a statistically significant reduction in mortality from stroke, reducing the death rate to approximately in half (10% vs 19%).

The EXTEND-IA trial was sponsored by the National Stroke Research Institute of Australia and was conducted at medical centers in Australia and New Zealand. Bruce C.V. Campbell, MD, et al published the EXTEND-IA results online ahead of print in the The New England Journal of Medicine.

Medtronic stated that the EXTEND-IA trial, which was composed of 70 patients, showed a statistically significant improvement in the rate of return to functional independence (71% vs 40%) in favor of patients treated with the Solitaire device compared to patients treated with IV-tPA alone. EXTEND-IA showed a strong, but not statistically significant, trend toward reduction in death from stroke (9% in the Solitaire arm vs 20% in the IV-tPA alone arm). In addition, patients treated with Solitaire spent statistically significantly less time in the hospital or in rehabilitation before returning home/to work (15 vs 73 days). The study realized a statistically significant improvement in recanalization rates at 24 hours of 100% with Solitaire versus 37% with IV-tPA alone, advised Medtronic.

The company advised that both the ESCAPE and EXTEND-IA trials were stopped early by the safety committee due to the strength of the results, indicating the benefit of stent thrombectomy with the Solitaire device. Designed to restore blood flow to the brain of patients with ischemic stroke, the Solitaire device provides an alternative treatment to patients. Many patients are ineligible for IV-tPA either because they have missed the 0- to 3-hour window for treatment to commence or because they experience a large vessel occlusion or acute ischemic stroke, in which case blood clots are too large to dissolve with pharmaceutical treatment, making stent thrombectomy the most viable treatment option.

The company stated that ESCAPE and EXTEND-IA have confirmed the findings of MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands). MR CLEAN was recently published by Olvert A. Berkhemer, MD, et al in The New England Journal of Medicine (2015;372:11–20).

Dr. Campbell, who is with the University of Melbourne in Australia, commented in Medtronic’s press release, “The landmark results of ESCAPE and EXTEND-IA indicate that a profound change in how we provide stroke care is needed. Our findings provide overwhelming evidence of the safety and efficacy of stent thrombectomy.” Dr. Hill, who is with the University of Calgary, added, “We now have an irrefutable body of clinical evidence with a broad patient base supporting the use of endovascular treatment, particularly when stent thrombectomy is used. Guidelines will change.”