For example, nusinersen, an exon-inclusion 2′-O-Metoxyethyl-modified ASO, was approved by the U.S. FDA in 2016 for the treatment of spinal muscular atrophy (SMA), a devastating neuromuscular disease that is caused by the loss of function of the survival motor neuron 1 (SMN1) gene [11]. This evidence concerns the gene SMN1 and proximal spinal muscular atrophy.