Timing of Levodopa Treatment in Parkinson's Disease
Timing of Levodopa Treatment in Parkinson's Disease
The ELLDOPA study is a controlled clinical trial in patients with newly diagnosed PD to
 determine the optimal timing and dosing with levodopa (Sinemet or its generic equivalents).
The time to begin levodopa therapy has been controversial for many years, and yet every
 patient with PD, along with his/her treating doctor, needs to make this decision. One school
 of thought is that levodopa may lead to developing motor fluctuations and involuntary
 movements, and therefore its introduction should be delayed. The opposing school of thought
 argues that it is the worsening severity of the disease over time that makes the patient
 susceptible to these problems, and argues that the best response to levodopa is in the early
 stages of the illness when an improved quality of life can be optimized with levodopa.

 Another debated issue is whether levodopa offers protection or is harmful to the remaining
 dopamine neurons. The latest studies in tissue culture show that when glia (the brain's
 supportive cells) tissue is present in addition to the nerve cells, the glia tissue becomes
 protective against any levodopa toxicity. Because glia tissue is present in brain, the
 argument has been made that levodopa should not be toxic in living brain tissue. A few
 studies have been carried out in animal models of PD. Two of these animal studies suggest
 levodopa is toxic to neurons, and two show that levodopa is not toxic and may actually have a
 protective effect. So there is no convincing or consistent evidence that levodopa damages
 dopamine neurons in humans or animal models of PD.

 With this uncertainty as to what levodopa may be doing to the remaining dopamine cells in
 patients with PD, there is a strong need to make the determination in patients as to whether
 levodopa protects or worsens the progression of PD.

 Primary End Point: Progression of PD as determined by change in a PD rating scale, the UPDRS,
 between baseline examination and examination at Week 42. These two examinations are conducted
 by a Primary Rater who sees the subjects only twice: at baseline and at Week 42, so as not to
 be influenced by any effects the subject may have experienced during the 40 week exposure to
 investigational medication.
Inclusion Criteria:

 -  Early, mild PD, not requiring medications

 -  Age 30 or older

 -  Duration from time of diagnosis of PD: less than 2 years

 -  Hoehn & Yahr Stage 1 or 2

 -  Exposure to levodopa or dopamine agonist of 14 days or less