For instance, Aviles-Olmos and colleagues demonstrated in a single-blinded trial (evaluation of most motor symptoms on a video, by a blinded neurologist) that treatment of moderately advanced PD with the once-weekly glucagon-like peptide 1 (GLP1)-agonist exenatide for 12 months led to better motor and cognitive scores in the 20 treated patients than in the 24 controls [20]. This evidence concerns the gene GLP1R and Parkinson disease.