However, consistent with promising pre-clinical data in Parkinson's disease models after vector-mediated overexpression of glial-derived neurotrophic factor (GDNF, Axelsen and Woldbye, 2018), Brain Neurotherapy Bio is preparing for a randomized, double-blinded, placebo-controlled phase 1 trial with symptomatic AAV2-GDNF gene therapy delivered bilaterally to the putamen of adult MSA patients (NCT04680065). This evidence concerns the gene GDNF and Parkinson disease.