Study tracks clot removal’s effectiveness at treating strokeSep. 19, 2013, 8:53 AM
Over the past decade, neurointerventionalists have refined techniques for manually removing blood clots causing stroke. Now they are joining forces for a clinical trial to demonstrate the safety and effectiveness of the techniques.
The “Perfusion Imaging Selection of Ischemic Stroke Patients for Endovascular Therapy,” or POSITIVE trial, will include 750 patients at 20 centers around the United States.
J Mocco, M.D., M.S., associate professor of Neurological Surgery at Vanderbilt University Medical Center, is one of four primary investigators of the study, along with physicians at the University at Buffalo (UB), Stony Brook University and the Medical University of South Carolina (MUSC). Vanderbilt is the clinical research organizing site, while MUSC is the overall coordinating center.
The study will compare the safety and outcomes of mechanical thombectomy (clot removal) over medical therapy for treating acute ischemic stroke in patients who are ineligible for intravenous tissue plasminogen activator (tPA), the clot-busting drug.
IV-tPA must be administered within three hours of stroke symptom onset and has other exclusionary criteria, including previous surgery and taking certain medications.
“Currently only between 4-7 percent of patients who have strokes are eligible for IV-tPA. So the big picture is that over 90 percent of patients don’t have any proven recanalization therapy options,” Mocco said.
“I think the evidence suggests that going in and removing the clot is beneficial. I believe wholeheartedly that it is beneficial. But there is an onus, an obligation, on us to prove that benefit in the context of a prospective, randomized trial like this.”
Patients will be randomized to receive either standard-of-care medical therapy or mechanical intervention, which includes various FDA-approved devices.
Some use a stent-shaped device to engage and remove the clot. Others use an aspiration catheter, like a straw, to suck out the clot.
The $7.6 million study is funded by three different device manufacturers.
“It’s not device-specific or allowing one company to advocate for the use of their technology. We’ve gotten every company with a stroke device to contribute equally to fund the trial. It’s a unique collaboration,” Mocco said.
Stroke is a leading cause of death in the United States, killing nearly 130,000 each year, according to the Centers for Disease Control and Prevention. It is more common in the “stroke belt” southern states.
Mocco hopes positive results from this trial will spread interventional stroke techniques nationwide.
“We want to confirm our belief that this is beneficial and help the many thousands of patients who don’t even have a shot right now because it isn’t adopted nationally across the board,” Mocco said. “The goal is to follow the trauma model and have centers with the expertise and funnel patients there very quickly for this type of treatment. It’s about saving lives and giving people a higher level of functionality.”
The other primary investigators are Aquilla Turk, D.O., at MUSC; David Fiorella, M.D., Ph.D., at Stony Brook; and Adnan Siddiqui, M.D., Ph.D., at UB.