Results from the trial were published in the New England Journal of Medicine, the Kalamazoo, Mich.-based company said.
“By quadrupling the size of the therapeutic time window, the consequence of Dawn is that many more patients with large vessel occlusion stroke have the potential to be treated with mechanical thrombectomy. Dawn validates the physiological, rather than time-based approach to patient selection for endovascular therapy,” co-principal investigator Dr. Tudor Jovin of the University of Pittsburgh Medical Center said in a prepared statement.
In the Dawn trial, researchers compared treatment using the Trevo thrombectomy device in addition to clot-busting drugs with the drugs alone between 6 and 24 hours after stroke patient was last known to be well.
Results indicated that patients treated with the thrombectomy device within six to 24 hours after stroke had better disability and functional independence outcomes at 90 days when compared to standard medical care.
“For every two patients who underwent thrombectomy, one additional patient had a better score for disability at 90 days (as compared with the results in the control group); for every 2.8 patients who underwent thrombectomy, 1 additional patient had functional independence at 90 days,” researchers wrote in the study discussion. “The benefit of thrombectomy was consistent across prespecified subgroups that were defined according to age, stroke severity, occlusion site, time to treatment, and type of stroke onset, but the power of the trial to assess differences between subgroups was limited.”
Stryker said that currently less than one in 10 patients who suffer from an ischemic stroke receive thrombectomy treatment due to a lack of evidence supporting the use of such devices and that results from the trial could increase the use of such devices.
“Time alone should no longer be a disqualifier for thrombectomy but rather only a source of urgency. We hope this new treatment paradigm will benefit a large proportion of patients who were previously deemed untreatable,” co-principal investigator Dr. Raul Nogueira of the Grady Memorial Hospital said in a prepared release.
The company paid $135 million for Concentric Medical and its Trevo clot retriever back in 2011. The device is designed to remove the blood clots that cause ischemic stroke.
“The results of the Dawn Trial offer the first level-one evidence of significant reduced disability in patients who present in the late time window. However, best outcomes are achieved when patients are treated as quickly as possible, requiring increased patient awareness, EMS outreach and hospital infrastructure to be in place,” Stryker neurovascular division prez Mark Paul said in a press release.
Stryker paused enrollment in the Dawn trial in March after a review board decided there’s a high probability of success for the study.
The company said it halted enrollment in the 500-patient Dawn trial after signing on just 200 patients after a scheduled review by the study’s independent Data Safety Monitoring Board.