NCT06742450 is a randomized, parallel-controlled, multi-center clinical trial comparing constant current (CC) versus constant voltage (CV) modes of deep brain stimulation (DBS) in patients with Parkinson's disease. The study aims to compare efficacy, programming burden, power consumption, and physician/patient satisfaction between the two stimulation modalities.
Deep brain stimulation (DBS) has revolutionized the treatment of advanced Parkinson's disease, providing significant improvements in motor function, medication reduction, and quality of life for patients who have exhausted optimal medical therapy. Despite its widespread adoption, fundamental questions remain about optimal stimulation parameters and hardware configurations. This trial addresses one such critical question: whether constant current or constant voltage stimulation provides superior clinical outcomes.
NCT06742450 is a randomized, parallel-controlled, multi-center clinical trial comparing constant current (CC) versus constant voltage (CV) modes of deep brain stimulation (DBS) in patients with Parkinson's disease. The study aims to compare efficacy, programming burden, power consumption, and physician/patient satisfaction between the two stimulation modalities.
Deep brain stimulation (DBS) has revolutionized the treatment of advanced Parkinson's disease, providing significant improvements in motor function, medication reduction, and quality of life for patients who have exhausted optimal medical therapy. Despite its widespread adoption, fundamental questions remain about optimal stimulation parameters and hardware configurations. This trial addresses one such critical question: whether constant current or constant voltage stimulation provides superior clinical outcomes.
| Field | Value |
|-------|-------|
| NCT Number | NCT06742450 |
| Status | Recruiting |
| Phase | Not Applicable (Device Study) |
| Enrollment | 180 participants (estimated) |
| Study Type | Interventional |
| Allocation | Randomized |
| Intervention Model | Parallel |
| Masking | Double-blind (Participant, Outcomes Assessor) |
| Start Date | January 27, 2024 |
| Primary Completion | March 31, 2026 |
| Completion Date | August 31, 2026 |
| Sponsor | Xuanwu Hospital, Beijing |
| Collaborators | Beijing Pins Medical Co., Ltd; Chinese PLA General Hospital; Tianjin Huanhu Hospital; and 10 additional sites |
Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an established treatment for advanced Parkinson's disease[@dbs_mechanisms][@stn_dbs_outcomes]. The therapy delivers electrical pulses to targeted brain regions, modulating abnormal neural activity and restoring more normal motor circuit function. Two primary stimulation modalities are available:
The traditional approach used in most DBS systems, constant voltage mode maintains a fixed voltage output at the electrode-tissue interface[@volkmann2013]:
A more recent innovation, constant current mode maintains a fixed current output regardless of impedance changes[@constant_current_dbs]:
This head-to-head comparison is clinically significant because:
For subjects who have decided to undergo STN-DBS surgery and meet inclusion criteria, the constant current (CC) mode is selected as the stimulation modality one week after surgery. Regardless of any changes in programming parameters over the following year, the constant current (CC) mode will be maintained. Participants will undergo standard postoperative programming sessions to optimize their therapeutic window.
For subjects who have decided to undergo STN-DBS surgery and meet inclusion criteria, the constant voltage (CV) mode is selected as the stimulation modality one week after surgery. Regardless of any changes in programming parameters over the following year, the constant voltage (CV) mode will be maintained.
Both groups undergo identical surgical procedures:
| Measure | Timeframe | Description |
|---------|-----------|-------------|
| MDS-UPDRS I | 6 months | Non-motor experiences of daily living |
| MDS-UPDRS II | 6 months | Motor experiences of daily living |
| MDS-UPDRS IV | 6 months | Motor complications (dyskinesias, fluctuations) |
| Clinical Global Impression (CGI) | 6 months | Overall clinical assessment |
| Physician satisfaction feedback | 6 months | Structured programming experience survey |
| Patient satisfaction feedback | 6 months | Treatment experience questionnaire |
| Power consumption | 6 months | Device battery metrics |
| Impedance measurements | 6 months | Electrode-tissue impedance |
| Adverse effects | 12 months | Safety monitoring |
| Visit | Timing | Assessments |
|-------|--------|-------------|
| Screening | Pre-surgery | Medical history, cognitive assessment, imaging |
| Surgery | Day 0 | Bilateral STN-DBS implantation |
| Activation | Day 7 | Device activation, initial programming |
| Month 1 | Week 4 | Clinical assessment, optimization |
| Month 3 | Week 12 | Primary and secondary endpoints |
| Month 6 | Week 24 | Comprehensive outcome assessment |
| Month 12 | Week 48 | Final safety assessment |
Imaging Biomarkers
Potential Benefits of Each Mode
| Aspect | Constant Current | Constant Voltage |
|--------|-----------------|------------------|
| Dose stability | Consistent over time | Varies with impedance |
| Programming ease | May need less adjustment | Requires impedance monitoring |
| Battery life | Variable | Often longer at low impedance |
| Flexibility | Fixed current, variable voltage | Fixed voltage, variable current |
| Clinical data | Growing evidence | Extensive long-term data |
Challenges
DBS impacts multiple domains of quality of life[@rektorova2015]:
Motor Benefits
STN-DBS Efficacy
Multiple randomized controlled trials have demonstrated STN-DBS efficacy[@Deuschl2006][@morrell2011]:
| Device | Manufacturer | Current Mode | Voltage Mode | Key Features |
|--------|-------------|-------------|--------------|---------------|
| RC | Boston Scientific | Yes | Yes | Directional leads |
| Infinity | Abbott | Yes | Yes | Bluetooth programming |
| Activa | Medtronic | No | Yes | Longest clinical history |
| Pins | Beijing Pins | Yes | Yes | Chinese manufacturer |
The field of DBS continues to evolve: