Monitoring the Spread of Putaminal Gene Therapy for Parkinson Disease

The enzyme aromatic L-amino acid decarboxylase (AADC) is required to convert levodopa to dopamine; this enzyme is deficient in Parkinson disease (PD). To investigate the safety of administering adeno-associated viral vector serotype-2 carrying complementary DNA encoding AADC (VY-AADC01) for moderately advanced PD, researchers conducted a phase 1, partially manufacturer-funded study. They enrolled 15 subjects to receive gene therapy with VY-AADC01. The gene therapy was coadministered bilaterally with gadoteridol into the putamen. Intraoperative MRI was used to visualize the spread of the infused therapy. There were three cohorts of five patients each. Cohort 1 received 8.3 × 10¹¹ vector genomes (vg)/mL and ≤450 μL per putamen (total dose, ≤7…