---
title: Restore glucocerebrosidase activity in putamen
nct_id: NCT05565443
phase: NA
status: RECRUITING
sponsor: InSightec
study_type: INTERVENTIONAL
canonical_url: "https://parkinsonspathways.com/trial/NCT05565443"
clinicaltrials_gov: "https://clinicaltrials.gov/study/NCT05565443"
last_fetched: "2026-05-10T14:07:05.145Z"
source: "Parkinson's Pathways (curated)"
---
# Restore glucocerebrosidase activity in putamen

**Goal (in five words):** Restore glucocerebrosidase activity in putamen

**Official Title:** A Phase I/II Study for Bilateral Putamenal Delivery of Recombinant Glucocerebrosidase in Patients With Parkinson's Disease Using MR-guided Focused Ultrasound Induced Opening of the Blood-brain Barrier

**Trial ID:** [NCT05565443](https://clinicaltrials.gov/study/NCT05565443)

## Key Facts

- **Phase:** NA
- **Status:** RECRUITING
- **Study Type:** INTERVENTIONAL
- **Sponsor:** InSightec
- **Target Enrollment:** 14 participants
- **Start Date:** 2022-11-30
- **Completion Date:** 2027-12-31
- **Conditions:** Parkinsons Disease
- **Interventions:** Blood Brain Barrier Disruption - Functional
- **Intervention Types:** DEVICE

## Summary For Families

The goal is to get the enzyme glucocerebrosidase into the putamen to fix lysosomal problems that can drive alpha-synuclein buildup, potentially slowing disease processes that are linked to GBA gene mutations. The team uses MRI-guided focused ultrasound to temporarily open the blood brain barrier over both putamen areas so intravenously delivered recombinant glucocerebrosidase can reach brain cells, where it should boost GCase activity and help clear misfolded proteins; it is given in addition to a person’s usual Parkinson’s medications, not as a replacement for levodopa. Adults 35 to 80 years old with Parkinson’s for at least 2 years, Hoehn and Yahr stage 1,3 on medication, a positive DAT SPECT, and stable PD meds are eligible, with one arm for people who carry at least one GBA mutation and another arm for those with two normal GBA alleles.

## Eligibility

- **Minimum age:** 35 Years
- **Maximum age:** 80 Years
- **Sex:** ALL

### Full Criteria

```
Inclusion Criteria:

* Men or women between age 35 and 80 years, inclusive.
* Able and willing to give informed consent.
* Diagnosis of PD satisfying MDS Clinical Diagnostic Criteria for PD
* At least 2 years from initial diagnosis
* Hoehn and Yahr Stage 1-3 on PD medication
* Dopaminergic deficit by a positive DAT SPECT scan
* On stable regimen of PD medications for at least 90 days prior to the study
* American Society of Anesthesiologists (ASA) score 1-3
* Harbor at least one GBA mutation if enrolled in the GBA PD arm or two wild-type GBA alleles if enrolled in the idiopathic PD arm

Exclusion Criteria:

* Positive pregnancy test (for pre-menopausal women).
* Contraindication to DEFINITY ultrasound contrast agent or perflutren (e.g. hypersensitivity, known left or bidirectional cardiac shunt)
* Contraindication to MRI or gadolinium-DTPA (e.g. incompatible device, hypersensitivity)
* Insulin-dependent diabetes mellitus that is not well-controlled or that in the Investigator's opinion precludes participation in the study.
* Severely impaired renal function with estimated glomerular filtration rate \<30 mL/min/1.73m2 and/or on dialysis.
* Currently participating in another clinical therapeutic trial
* Patient receiving bevacizumab (Avastin) therapy
* Subjects with evidence of cranial or systemic infection.
* Cerebral or systemic vasculopathy.
* Documented cerebral infarction within the past 12 months or TIA in the past 1 month.
* Contraindication to GCase enzyme therapy, specifically previous hypersensitivity reaction to GCase enzyme therapy
* Parkinsonism plus symptoms, secondary parkinsonism
* Previous neurosurgical procedure for PD
```

## Locations (1)

- Sunybrook Research Institute, Toronto, Ontario, Canada _(43.7064, -79.3986)_
  - Inthuja Suthananthan — (CONTACT) — 647-687-8062 — inthuja.suthananthan@sri.utoronto.ca
  - Nir Lipsman, M.D., Neurosurgery — (PRINCIPAL_INVESTIGATOR)

## Central Contacts

- Alyssa Voelker-Christy — (CONTACT) — +1-817-948-5219 — alyssav@insightec.com

---

*Canonical: https://parkinsonspathways.com/trial/NCT05565443*  
*HTML version: https://parkinsonspathways.com/trial/NCT05565443*  
*Source data: https://clinicaltrials.gov/study/NCT05565443*