SMN1 and proximal spinal muscular atrophy: However, Spinraza® (nusinersen, an antisense oligonucleotide-based SMN protein-enhancing therapy) and Zolgensma® (onasemnogene abeparvovec-xioi, adeno-associated virus vector-based SMN1-gene therapy) have been approved by regulatory agencies in multiple countries, including the U.S. and Japan, as treatment choices for SMA.