Clinical Trial: Ultrasound technology and magnetic-resonance imaging to disrupt the blood-brain barrier in the fight against Alzheimer's Disease
By Lauren Keating
Researchers are currently conducting a study that could revolutionize treatment and bring newfound hope for Alzheimer's disease patients.
Conducted by Florida Atlantic University Institute for Human Health and Disease Intervention (I-Health) and Delray Medical Center, this groundbreaking clinical trial uses ultrasound technology and magnetic-resonance imaging to disrupt the blood-brain barrier and reduce the buildup of protein that may be linked to the disease.
"In dealing with Alzheimer's disease— like many brain disorders—one of the difficulties is getting therapeutic agents into the brain," the study's director Gregg B. Fields, Ph.D. said.
"Any drug you may have that you wish to target for a brain disorder could be used with this technology."
The goal of the clinical trial, ExAblate Blood-Brain Barrier (BBB) Disruption for the Treatment of Alzheimer's Disease, is to assess the safety and effectiveness of using ultrasound technology in Alzheimer's patients.
According to Dr. Fields, executive director of I-Health and a professor of chemistry and biochemistry at FAU's Charles E. Schmidt College of Science, the blood-brain barrier exists to prevent harmful molecules from getting inside the organ.
"There's two things about this technology that I think are potentially just game-changing, as they say,"
Dr. Fields said. The first is the technology's ability to open the blood-brain barrier.
Pharmaceuticals usually cannot pass through the blood-brain barrier or do so poorly. To change this and increase the effectiveness of Alzheimer's disease drugs, researchers use ultrasound technology to inject the brain with tiny, gas-filled lipid spheres called microbubbles that circulate in the brain. When the ultrasound is applied, the bubbles expand and open up the blood-brain barrier in very specific regions based on where the researchers aim. As a result, this can improve drug delivery to specific parts of the brain.
"Any drug you may have that you wish to target for a brain disorder could be used with this technology,"
Dr. Fields said. "Right now, our clinical trial is based on Alzheimer's patients. But as you can imagine, you can go to people who have brain cancer and utilize certain therapeutic agents that would normally help them but are very difficult to get across the blood-brain barrier. So it has a wide variety of potential applications."
The second factor that makes this FDA-approved clinical trial so impressive is that the treatment is non-invasive.
The patient wears a helmet while inside an MRI to receive the treatment. The researchers teamed with medical device company Insightec to develop this tech called ExAblate Model 4000 Type 2.0.
Insightec's FDA-approved technology is currently used to treat tremors in those with Parkinson's disease.
The treatment takes about three hours, and patients receive a total of three treatments administered two weeks apart. Study participants are then monitored for five years. The first patient to get the treatment was on February 15 to 23, 2023. The second treatment was administered on March 1. The patient did not get the final treatment because of some cognitive decline. This was found to be linked not to the treatment but to the patient not being compliant with taking their drugs.
Patient compliance is an issue because some are not on top of taking their medication, either by choice or by accident. Forgetfulness is associated with the disease. Researchers currently have several patients in the initial screening process, which includes evaluating cognitive state and the relative amount of beta-amyloid they have in the brain.
While there is still no known cause of Alzheimer's disease, Dr. Fields said what does exist are diagnostic features of Alzheimer's. These include two proteins that "misbehave"
in the brain. One that's very distinct is the buildup of beta-amyloid. The other is the protein referred to as Tau, known for aggregating inside cells and killing neurons.
The researchers are looking at those in the early stage of cognitive decline to participate in the trial.
There are currently five patients who are at the PET scan screening stage, making them a step closer to being eligible for this groundbreaking treatment. While this treatment may not be a cure for Alzheimer's, it's still promising. "We're not really looking for improvement of cognition, he said. "We're looking for a slowing down of decline."
The goal is to manage the disease and stabilize patient's cognitive function so they can live longer, healthier lives with the disease. However, this is based on the current drugs available.
Dr. Fields said Lecanemab is a commonly used drug at the moment, but it may be phased out to feature a drug called Leqembi. "Both of those drugs do the same thing, but one is more effective than the other," he said.
"Its goal is to clear out the beta-amyloid from the brain."
It may very well come a day when a drug hits the market that targets the mechanism of how Alzheimer's starts. The effect could then be different.
There are about 6.5 million Americans with Alzheimer's disease ages 65 and older. Florida has the second-highest amount of cases of Alzheimer's in the U.S. Genetics and lifestyle factors play a role in Alzheimer's disease occurrence. According to Dr. Fields, those who are diabetic or suffer from inflammation have a higher risk of Alzheimer's disease. The clinical trial's current goal is to create a safety profile for 25 patients. Dr. Fields said the FDA isn't too far away from opening the trial to more patients.