A major study into the progression of Parkinson's disease is being launched by actor Michael J Fox.
The research is the first of its kind and will involve 400 people from five sites in Europe and 14 hospitals in the US.
Patients in the earliest stages of Parkinson's -- before they have started any treatment -- will be enrolled in the study to find key biomarkers for the disease.
Fox (49) who was diagnosed with young-onset Parkinson's aged 30, said the research was important because "better treatments aren't going to fall from the sky" and "real challenges stand in the way of the results we need".
Currently, there is no definitive way of measuring how Parkinson's progresses.
This means it is difficult for doctors to work out whether a drug is slowing down or halting the disease's advance.
Reliable and robust biomarkers to monitor the progression of Parkinson's would improve patient care, lead to new drugs and enhance understanding of the condition.
Symptoms include a tremor or fine shake while the person is at rest, rigidity of muscles, slowness of movement and unsteady balance.
In the new study, samples taken from patients will help identify what is happening in the body, and will include data on motor skills, samples of blood, urine and spinal fluid, and brain scans. This data will be then used either alone or in combination to track progression of the disease.
The research starts in early 2011 and is being co-ordinated and part-funded by the Michael J Fox Foundation for Parkinson's Research.