February 17, 2023 – Butylphthalide, a recent drug derived from celery seeds, could improve outcomes after a stroke attributable to a blood clot when given along with immediate treatment of the clot, based on a new study.
Patients who received this treatment had fewer severe brain symptoms and higher each day functioning 90 days after the stroke than patients who received clot treatment and a placebo.
Butylphthalide is approved and available in China, where the study was conducted, however the drug has not been approved to be used by the FDA.
“This is the first trial to show the benefit of a drug that protects the brain from damage caused by a lack of oxygen to brain tissue. The drug was given to patients with acute ischemic stroke who were also receiving treatment to restore blood supply to the brain,” says co-author Baixue Jia, MD, an interventional neuroradiologist at Beijing Tiantan Hospital and the China National Clinical Research Center for Neurological Diseases in Beijing.
“Patients who received butylphthalide had less severe neurological symptoms and better life status 90 days after the stroke than those who received the placebo,” says Jia. “If the results are confirmed in other studies, this could lead to more treatment options for strokes caused by blood clots.”
The results were presented on the International Stroke Conference of the American Stroke Association.
In China, previous animal studies found that butylphthalide can protect the brain from damage attributable to a stroke attributable to a blood clot within the brain. Human trials have now begun.
Jia and colleagues investigated whether treatment with butylphthalide could improve 90-day outcomes in adults who were also receiving standard clot treatment, reminiscent of an intravenous clot-dissolving drug called tissue plasminogen activator (tPA), mechanical clot removal, or each.
Patients were treated at one among 59 medical centers in China between 2018 and 2022. In addition to the initial blood clot treatment chosen by their doctor, they were randomly assigned to receive either butylphthalide or a “similar” placebo, given as each day injections for the primary 14 days after which as oral capsules for 76 days. Neither patients nor researchers knew how the study participants were allocated.
The research team defined outcomes as “favorable” if a patient fell into one among these categories 90 days after the stroke: an initial mild to moderate stroke and no symptoms after treatment; an initial moderate to severe stroke and no symptoms or mild symptoms that didn't prevent them from performing each day activities after treatment; or an initial severe to severe stroke and no symptoms or mild disability that interfered with some activities after treatment.
Of the 1,216 patients, 607 received butylphthalide and 609 received placebo. The average age was 66 years and 68% were men.
Overall, the likelihood of a good 90-day consequence was 70% higher amongst those within the butylphthalide group in comparison with the placebo group.
Butylphthalide also improved function in all patients, including those that received tPA first, those that had the blood clot removed mechanically, and people who received each.
There were no significant differences between the 2 groups in other outcomes reminiscent of recurrent strokes and cerebral hemorrhages.
Further studies are needed, the study authors noted. Researchers don't yet understand how butylphthalide works within the body or how stroke patients respond once they receive treatments apart from tPA or mechanical clot removal.
“Although these are interesting results, this is a relatively small study in a fairly select population in China,” says Daniel Lackland, DrPH, professor of neurology and director of the Division of Translational Neuroscience and Population Studies on the Medical University of South Carolina.
Lackland, who was not involved within the study, is a member of the American Stroke Association's Stroke Council. He cautions against directly linking butylphthalide to celery seed or celery seed extract supplements.
“Although this derivative, which appears to be effective, is derived from celery seed, it is not the same as eating celery seed,” he says. “So we don't want to look at celery seed and say, 'OK, I'm going to do this therapy that has been shown to improve recovery after a stroke.' It's not the same thing. Stroke patients should always consult their neurologist or doctor about diet after a stroke.”