The authors also report some hints of efficacy. For example, various motor functions appear improved over the course of the study. As the authors point out, however, the study was uncontrolled, and the road to effective neuroprotection strategies in Parkinson's disease is littered with casualties. And there are many reasons to greet these results with caution. First, imaging performed in concert with the study is not consistent with a therapeutic effect. Second, a major concern with studies like this is whether they produce symptomatic treatment, or whether they actually stem neurodegeneration. Disentangling the two presents an extraordinary scientific and biostatistical problem. Third, a relationship between dose and response does not seem to have been observed.
Still, the case for proceeding to phase 2 studies- to this observer at least- looks credible (photo credit: brunsdon 2007)