New technology that uses MRI-guided focused ultrasound to target areas of the brain affected by Parkinson’s disease and improve motor symptoms will be further tested in a pivotal Phase 3 clinical trial.
Led by the University of Maryland Medical Center (UMMC) and the University of Maryland School of Medicine (UMSOM), the randomized trial will assess the safety and effectiveness of the novel procedure. It is the final step before the U.S. Food and Drug Administration (FDA) will consider approving it as a nonsurgical treatment for Parkinson’s.
“The goal of the focused ultrasound treatment is to both lessen the main symptoms of Parkinson’s disease, which include tremors, rigidity and slow movement, as well as treat the dyskinesia that is a medication side effect, so that less medication is needed,” Howard M. Eisenberg, MD, the trial’s lead investigator, said in a press release. Eisenberg is a professor and the chair of neurosurgery at both UMSOM and UMMC.
Participants are currently being recruited for the new trial (NCT03319485), which follows a previous study where MRI-guided focused ultrasound led to a 62% improvement in upper-limb tremors, compared with 22% in the control group, in patients with tremor-dominant Parkinson disease who did not respond to other forms of therapy.
Findings were published in the study, “Safety and Efficacy of Focused Ultrasound Thalamotomy for Patients With Medication-Refractory, Tremor-Dominant Parkinson Disease: A Randomized Clinical Trial,” in the journal JAMA Neurology.
“The results of the pilot trial, so far, are very encouraging,” said Eisenberg about the first trial conducted in 2015 with 20 patients, the majority of whom were treated at UMMC.
With the new technology, clinicians direct ultrasound waves to a brain structure called the globus pallidus, which helps regulate voluntary movement, to destroy damaged tissue, decreasing the uncontrolled movements that characterize Parkinson’s disease.
Doctors use magnetic resonance imaging (MRI) to create a temperature map of the brain, giving them a real-time picture of the region they want to hit with the sound waves. They then raise the energy, directly targeting that area of the brain to destroy the tissue.
Patients are awake and alert the entire time in the MRI scanner, enabling them to give clinicians constant feedback. They are fitted with a helmet through which the energy is converted into sound waves, which are then targeted to the globus pallidus. The approach is noninvasive, meaning there is no surgery or radiation treatment involved.
Current therapies to lessen movement and coordination problems in Parkinson’s patients include levodopa (sold under the brand name Dopar, among others), which is the most common. Patients with advanced Parkinson’s may undergo surgery, known as deep brain stimulation, to implant micro-electrodes in the brain that help control tremors, rigidity and dyskinesia (abnormal, uncontrolled, involuntary movement).
“For people with Parkinson’s disease and other movement disorders such as essential tremor, focused ultrasound is an appealing alternative to deep brain stimulation because it does not involve more invasive surgery,” said Paul S. Fishman, MD, PhD, professor of neurology at UMSOM and a neurologist at UMMC.
Enrollment in the study is approximately 80 to 100 participants, and the inclusion criteria were designed to include a wider population of Parkinson’s patients. Sponsored by InSightec, the trial is recruiting participants in the U.S. at the University of Maryland Medical System, Maryland; Weill Cornell Medicine, New York; and The Ohio State Wexner Medical Center, Ohio.
“University of Maryland Medicine is a world leader in pioneering MRI-guided focused ultrasound to become a new standard of care for treating many devastating brain diseases including Parkinson’s, essential tremor and glioblastoma, an often deadly type of brain cancer,” said E. Albert Reece, MD, PhD, MBA, vice president of medical affairs at the University of Maryland and dean of UMSOM.