Researchers of a phase 3, prospective, open-label, single-arm trial (NCT04728295) across 9 centers tested staged, bilateral magnetic resonance–guided focused ultrasound (MRgFUS) pallidothalamic tractotomy for Parkinson’s disease (PD) with motor complications. Among 54 patients receiving unilateral treatment, Movement Disorder Society Unified PD Rating Scale Part III OFF scores improved by 50% (mean 20.9 to 10.0) and Part IV by 56.3% (10.5 to 4.6) at 3 months. Of 40 patients proceeding to staged bilateral therapy, Part III OFF improved 33.9%, with Part III OFF total scores improving 32% (mean 51.3 to 33.4; P<.0001); benefits were sustained through 12 months.
Safety was acceptable: after unilateral treatment, 30 related adverse events (AEs) occurred in 21 patients (87% mild; none severe), with 60% resolved by 6 months. After bilateral treatment, 43 AEs occurred in 22 patients (70% mild; 2% severe), with 40% resolved by 12 months. Common AEs included imbalance, dysarthria, and fatigue. The results, presented at the 2025 International Congress of Parkinson’s Disease and Movement Disorders, align with the FDA’s July approval of Insightec’s Exablate Neuro platform for staged bilateral pallidothalamic tractotomy, underscoring a noninvasive, incisionless option for advanced PD that avoids implanted hardware. Primary efficacy was defined as the change in Movement Disorder Society Unified PD Rating Scale Part III OFF bilateral upper and lower extremity score 3 months after the second procedure.
Reference: Ciccone I. Bilateral MR-Guided Focused Ultrasound Shows Benefit for Managing Parkinson Motor Complications in Phase 3 Trial. NeurologyLive. Published October 17, 2025. Accessed October 24, 2025. https://www.neurologylive.com/view/bilateral-mr-guided-focused-ultrasound-shows-benefit-managing-parkinson-motor-complications-phase-3-trial
