FAQs

In this section you'll find more information on the PD SURG trial.

Reasons for PD SURG

In Parkinson’s disease (PD), levodopa (LD) initially controls the symptoms of most patients, but after a few years of treatment motor complications develop. Dopamine agonists (DAs) or monoamine oxidase type B inhibitors (MAOBIs) have been used, either alone or with reduced doses of LD, in an attempt to delay the onset of motor fluctuations.

Once motor complications develop, DAs or MAOBIs may be introduced if not previously used, as may catechol-O-methyltransferase inhibitors (COMTIs), but in many patients these eventually fail to maintain adequate control of symptoms. At this point (or potentially earlier), surgical intervention may be considered. Surgery may be performed at three sites (thalamus, globus pallidum or subthalamic nucleus) using two techniques (radio frequency lesioning or electrical stimulation). There is very little reliable evidence available as to the optimal site, technique and timing of surgery. Few randomised trials have addressed these questions, and those that have been performed have been small. Most published reports relate to small non-randomised series, which can not provide reliable evidence because of the potential selection biases involved. There is, therefore, an urgent need for large randomised trials of surgery for PD to be undertaken.

How will it work?

The PD SURG trial will evaluate the role of subthalamic (STN) and pallidal (GPi) surgery, by either stimulation or lesioning, compared to medical therapy (with surgical intervention delayed as long as possible) in patients with advanced PD that is not adequately controlled by their current medical treatment. Patients allocated to medical therapy will receive whatever drug treatment is considered appropriate (this may include continuous apomorphine infusion). Although surgery may produce clear and rapid clinical improvements, it is also important to evaluate the safety and long-term effects of the procedure and to use endpoints of relevance to the patient

PDSURG is a large, simple, “real-life” trial that will determine reliably whether early surgery is more effective than deferred surgery for advanced PD.

Who's funding the study?

The research costs of the trial are funded by a grant from the UK Medical Research Council and UK Parkinson’s Disease Society awarded to the University of Birmingham.

When will we get results?

The first year results have been published, please see our publications page.

Further results will be made available when they have been completed.