Gene therapy approaches to Parkinson's disease: preclinical to clinical trials, or what steps to take to get there from here?

Do "gene therapies" offer new approaches to the treatment of Parkinson's disease? The presentations of this symposium, as well as numerous published articles, suggest that they might. This article describes a preclinical in vivo gene therapy study in parkinsonian monkeys and briefly reviews the history of studies with novel cellular implantation approaches to Parkinson's disease as a basis for evaluating when and how gene therapy trials in Parkinson's patients might be appropriate. A number of concerns are raised.