Using a "neuroprotectant" drug alongside the standard surgical removal of a clot may slash the risk of death and disability following a stroke, a new study finds.
The new medication, called ApTOLL, shields brain tissue from continuing damage by cooling down inflammation, the researchers said.
A stroke occurs when blood supply to part of the brain is blocked by a clot or when a blood vessel in the brain bursts. Ischemic strokes, which are far more common, occur when a blood clot cuts off blood supply to the brain.
Still, more research is needed before ApTOLL is ready for prime time.
“We need confirmatory studies in larger populations, and we are aiming to start those in the last quarter of 2023,” said study author Dr. Marc Ribó, an interventional neurologist at Hospital Vall d'Hebron in Barcelona, Spain. "If everything goes well and we replicate these findings in larger studies, the drug may be available in a couple of years.”
For the study, more than 150 people who had an ischemic stroke (average age, 70) were treated in 15 hospitals in France and Spain between July 2021 and April 2022. Patients received either 0.05 mg/kg of ApTOLL, 0.2 mg/kg of ApTOLL, or a placebo medication.
Everyone in the study also underwent mechanical blood clot removal to restore blood flow to their brain within six hours of the onset of stroke symptoms.
The result? The risk of dying from the stroke was four times lower among folks who received the higher dose of the drug when compared to those who received a placebo.
What's more, brain scans showed that the area of damaged brain tissue was reduced by 40% among those who received the higher dose of ApTOLL within 72 hours of treatment, compared to the placebo group.
Fully 64% of people who received the higher dose of ApTOLL didn't show signs of disability 90 days after their stroke. By contrast, this dipped to 47% among people in the placebo group, the researchers found.
“For the first time, a medicine studied as a neuroprotectant demonstrated not only a biological benefit by reducing the volume of damaged brain tissue, but also a reduction in long-term disability and risk of death,” Ribó reported.
Some people also received tissue-plasminogen activator (tPA) to help dissolve the blood clot in their brain. This drug is extremely effective at preventing lasting disability such as paralysis or speech issues after a stroke, but only if given within 4.5 hours of stroke onset, and the sooner, the better.
The new drug essentially hits pause on the damage cascade, widening the window in which tPA or surgery to remove the clot can be performed, Ribó noted. The goal is still to treat strokes as quickly as possible to stave off death and disability. Ribó explained that “tPA is fantastic, but time-dependent, and [it] does not affect muscle and tissues.”
The study was funded by AptaTargets S.L., which manufactures the drug. The findings were presented Wednesday at the American Stroke Association conference in Dallas. Such research should be considered preliminary until published in a peer-reviewed journal.
Stroke experts cautioned that this drug has many more hurdles to clear before, or if, it becomes readily available.
“Countless early-phase neuroprotective agents have failed to show benefit in larger, late-phase clinical trials,” said Dr. Andrew Russman, head of the Cleveland Clinic Stroke Program in Ohio. “The potential for this new medication remains unproven, [and] it will be several years before larger, definitive clinical trials are completed.”
If further studies validate the early findings, the drug may be an option for people who have had a stroke that blocks a major artery supplying blood to their brain and who are planning to undergo clot retrieval. The neuroprotectant would be given within six hours of the onset of symptoms in those scenarios, Russman said.
This agent needs to be tested more extensively before entering routine clinical care, agreed Dr. Joe Broderick, a professor of neurology and rehabilitation medicine at the University of Cincinnati's Gardner Neuroscience Institute, in Ohio.
"The data warrants further study in a phase 3 study, but differences seen in this trial may be due to small number of patients and imbalances in factors related to outcome," Broderick said, adding that a much larger trial would be needed to confirm the findings.
Dr. Deepak Bhatt, director of Mount Sinai Heart and professor of cardiovascular medicine at the Icahn School of Medicine in New York City, concurred.
“If a large confirmatory study is positive and shows this drug reduces death and disability from stroke in a much larger number of patients, it might be available in the future,” Bhatt said.
Learn to recognize stroke symptoms quickly at the American Stroke Association.
SOURCES: Marc Ribó, MD, interventional neurologist, Hospital Vall d'Hebron, Barcelona, Spain; Deepak Bhatt, MD, MPH, director, Mount Sinai Heart, Dr. Valentin Fuster Professor of Cardiovascular Medicine, Icahn School of Medicine, Mount Sinai Health System, New York City; Andrew Russman, DO, head, Cleveland Clinic Stroke Program, Cleveland, Ohio; Joe Broderick, MD, professor, neurology and rehabilitation medicine, University of Cincinnati, Gardner Neuroscience Institute, Cincinnati, Ohio; Feb. 8, 2023, presentation, American Stroke Association's International Stroke Conference, Dallas