Key Points
- Participants in an international clinical trial experienced a 32% improvement in the cardinal motor symptoms associated with Parkinson’s disease (PD).
- These data were considered by the US FDA in its 2025 approval of bilateral focused ultrasound for advanced PD.
A recent publication in Lancet Neurology indicates that focused ultrasound improves the motor symptoms and motor complications in patients with Parkinson’s disease (PD).
Three months after bilateral treatment, participants in a prospective, multicenter study experienced a 32% improvement in cardinal motor symptoms associated with PD, with benefits sustained through follow-up. In addition, motor complications (movement-related side effects from PD medications) improved by 67%. Adverse events were noted in more than half of bilateral participants.
This trial is the first to systematically evaluate staged, bilateral focused ultrasound treatment in PD. These data were considered by the US Food and Drug Administration (FDA) to approve the unilateral and staged, bilateral use of focused ultrasound for advanced PD in 2025.
The international clinical trial (NCT04728295) investigated the safety and efficacy of using bilateral MR-guided focused ultrasound to treat the motor symptoms of PD. Researchers at six centers in the US, two in Spain, and one Taiwan targeted the pallidothalamic tract (PTT), a system of nerve fibers involved in motor control.
Fifty-four participants (37 male and 17 female with an average age of 63 years) underwent focused ultrasound treatment with the Insightec Exablate Neuro device on the symptom-dominant side. After at least six months, participants who met appropriate criteria (40 of the 54) had the other side of the brain treated. In all, 36 participants completed 12 months of follow-up after the second procedure.
Unilateral focused ultrasound of the PTT was shown to be safe and efficacious for improving motor symptoms and motor complications in patients with PD. Motor function further improved following treatment of the second side, though the incremental benefit was less pronounced. Adverse events occurred in 39% of participants after unilateral treatment and 55% after second-side, or bilateral, treatment. One clinically significant event persisted at six months after the first procedure, and ten events persisted for at least one year after the second procedure.
The publication recommends that physicians exercise rigorous patient selection and counselling regarding cumulative risks before offering the second-side treatment of the PTT.
“This study represents an important milestone in the evolution of focused ultrasound treatment for PD and highlights the need for additional studies to confirm the effectiveness of the treatment and develop approaches to minimize its side effects,” said Foundation chairman Neal F. Kassell, MD.
According to Insightec, more than 30,000 patients have been treated with the Exablate device for a variety of movement disorder indications at 214 centers worldwide, including at more than 100 locations in the US.
This study was funded by Insightec.
See Media Coverage in NeurologyLive: Focused Ultrasound vs. DBS for Parkinson Disease: What New Bilateral Data Tell Us
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