The FDA has expanded the approval for the Trevo clot retrieval device to allow for thrombectomy up to 24 hours after the development of symptoms in patients with acute ischemic stroke.
Raul Nogueira, MD
The FDA has expanded the approval for the Trevo clot retrieval device to allow for thrombectomy up to 24 hours after the development of symptoms in patients with acute ischemic stroke, making it the only device approved for this time window. The device can be used in addition to tissue plasminogen activator (t-PA) therapy.
The decision was based on data from the DAWN clinical trial of 206 patients treated with either the device (n = 107) or with only medical management (n = 99). According to findings published in the New England Journal of Medicine, 49% of those treated with the device were functionally independent at 90 days compared with 13% in the control arm, representing a 33% improvement with the Trevo device.
"The 24-hour indication opens the treatment window to patients whose stroke would previously have progressed until all the brain tissue surrounding the affected arteries was dead, leaving them with a life of significant disabilities," Raul Nogueira, MD, of Grady Memorial Hospital and Emory University, said in a statement. "These patients now have a much better chance for an independent life without disability."
At baseline in the DAWN trial, the median NIHSS score was 17 across both treatment groups. The median infarct volume was larger in the control group, at 8.9 ml, compared with 7.6 ml in the Trevo arm. Median time from the last known absence of symptoms was 12.2 hours with Trevo versus 13.3 hours in the control group. Other baseline characteristics were well balanced across arms.
The mean Rankin scale at 90 days was 5.5 in the Trevo group compared with 3.4 in the control arm, for a Bayesian adjusted difference of 2.0 points. In a post-hoc sensitivity analysis, the Trevo device remained superior across subgroups.
Immediate reperfusion (mTICI scale grade 2b or 3) was achieved for 84% of patients in the Trevo group. The final median time interval from before the onset of symptoms to reperfusion was 13.6 hours. Early response was achieved for 48% of those in the Trevo group compared with 19% in the control group. Recanalization was achieved by 77% of those in the Trevo group at 24 hours compared with 36% in the control arm.
The rate of serious adverse events (SAEs) were similar between arms, which included death from stroke-related causes or any cause at 90 days (19% and 18%). Symptomatic intracranial hemorrhage occurred in 6% of patients treated with thrombectomy compared with 3% in the control group (P = .50). Neurologic deterioration was lower in the Trevo arm at 14% compared with 26% in the control group, for an absolute difference of -12 percentage points (P = .04).
“FDA clearance of the Trevo Retriever has effectively quadrupled the treatment window from 0 to 6 hours to 0 to 24 hours from time last seen well. Nonetheless, every minute still matters because in each individual patient, the earlier the blood flow is restored to the brain, the lower the resultant burden of permanent brain damage," Tudor Jovin, MD, University of Pittsburgh Medical Center, said in a statement. "Therefore, it is still imperative that all caregivers in the stroke pathway — from EMS to emergency room physicians to stroke neurologists to interventionalists – continue to deliver the fastest and most workflow-efficient treatment of stroke."
The Trevo device, which is manufactured by Stryker Neurovascular, was originally cleared in 2012 by the FDA for thrombectomy in patients with stroke that could not receive or did not respond to t-PA therapy. In 2016, the FDA expanded the indication to include certain patients in addition to t-PA therapy within 6 hours of symptom onset.
The device was also used in the DEFUSE 3 study, aiding in the recent updates to the America Heart Association/American Stroke Association guidelines, which recommends stent retrievers, such as Trevo. Between the DAWN and DEFUSE 3 trials, Trevo now has the largest cohort of data for a single device.
“Time is critical following the onset of stroke symptoms. Expanding the treatment window from 6 to 24 hours will significantly increase the number of stroke patients who may benefit from treatment,” Carlos Peña, PhD, the director of the division of neurological and physical medicine devices at the FDA’s Center for Devices and Radiological Health, said in a statement. “Health care providers and their patients now have better tools for treating stroke and potentially preventing long-term disability.”
Nogueira RG, Jadhav AP, Haussen DC, et al. Thrombectomy 6 to 24 Hours after Stroke with a Mismatch between Deficit and Infarct. N Engl J Med. 2018; 378:11-21.