Disease‐modifying approaches for Parkinson disease

377 W test, and strongly suspect is multifactorial, leading to significant heterogeneity. Two hundred years after its initial description, this is preciselywherewe find ourselves with Parkinson disease. By the time a patient is first diagnosed, there has been significant cell death and, as such, it seems likely that at best anydisease-modifying therapy will arrest or, more likely, only slow continued cell death. While data from the recent phase 2 study repurposing the diabetes treatment exenatide offer hope, the field has previously been disappointed by a catalogue of trials that have failed to translate into clinical practice. While clearly too brief, it is hoped that this article will provide the reader with some appreciation of this rapidly expanding topic.