Are Anti-Parkinsonian Treatments Disease Modifying?

Objective/Rationale:
Current treatments of Parkinson’s disease are not thought to slow the progression of the disease but just appear to result in temporary relief of symptoms. There is some evidence in recent clinical trials that both levodopa and rasagiline might slow progression and be considered disease modifying effects. However, controversy exists about the interpretation of the results. We think that analyzing these data with quantitative models for Parkinson’s disease will show if levodopa and rasagiline are indeed able to slow disease progression, resulting in a greater long term benefit to patients.
Project Description: 
The time course of changes in the Unified Parkinsons Disease Response Scale (UPDRS) in the ELLDOPA and TEMPO trials from the Parkinson’s Study Group will be analyzed in each patient to find out how quickly they progressed and what effects drug treatment had on the UPDRS and the rate of progression.
Relevance to Diagnosis/Treatment of Parkinson’s Disease: 
There have been long standing concerns that treatment with levodopa may worsen the progression of Parkinson’s disease. The ELLDOPA clinical trial was intended to test this idea but the results were inconclusive. The published analysis of ELLDOPA did not directly look at disease progression rates. We will quantify progression rates and determine directly if levodopa slows the disease.
Anticipated Outcome: 
We expect to confirm the predictions from DATATOP that both levodopa and rasagiline have disease modifying effects. With this new information we can give re-assurance to patients that these treatments can be helpful in the long term and are not making Parkinson’s disease progress more quickly. We will use the results to design better clinical trials to test new medicines that are being developed with the hope they can slow down, stop or even reverse the progression of the disease.