An experimental spinal cord stimulation (SCS) technique has delivered highly encouraging results in a trial for advanced Parkinson’s disease (PD), a progressive neurological disorder that affects movement control.
Spinal cord stimulation
Axial motor symptoms including gait dysfunction (walking abnormality), freezing of gait, and postural instability are common in patients diagnosed with PD for 10–15 years. Such symptoms significantly impair quality of life and compromise patients’ ability to live independently. Patients with advanced axial motor symptoms currently have limited treatment options.
They are often resistant to dopamine replacement therapy and experience limited benefits and unpredictable outcomes from deep brain stimulation techniques.
SCS is a technique that involves electrical stimulation of the spinal cord via electrodes implanted in the medial epidural space. It may promote restoration of normal neural activity in the primary cortex and dorsolateral striatum of PD patients by suppressing aberrant beta-frequency synchronous corticostriatal oscillations.
Western University in Canada study
Researchers at the Western University in Canada conducted a pilot study investigating the technique. The trial involved five male participants with advanced PD, including significant gait disturbances and freezing of gait, despite optimization of dopamine replacement therapy. The patients underwent SCS over 1–4 months. Patients demonstrated considerable improvements in motor control, which were maintained six months after discontinuation of therapy.
Freezing of gait episodes experienced by patients was significantly reduced and improvements in walking ability were also observed. By the end of the study, two participants who had needed assistance to walk were considered to be walking almost normally. A third patient reported discontinuation of wheelchair use in favour of a walking aid.
The findings of the study were described as “remarkable” by one of the researchers and have generated much interest among health care professionals and patients within the field. While the small scale of the study designates a cautious approach, the technique evidently has the potential to significantly improve the quality of life in advanced PD patients and could also reduce reliance on dopamine replacement therapy. The results of a larger ongoing trial comprising 25 patients are therefore eagerly anticipated. The study is expected to be completed by Q2 2020.
GlobalData (2019). Frontier Pharma: First-in-Class Innovation in Parkinson’s Disease and Behavioral Complications, to be published