So far, six AAV gene therapy products have already been approved for clinical use for non-cardiac indications, with over 1,400 patients having already been treated with onasemnogene55, an intravenously administered AAV9 vector expressing the survival of motor neuron 1 (SMN1) protein for spinal muscular atrophy (SMA). Here, SMN1 is linked to proximal spinal muscular atrophy.