Advances in drugs on targeting SMN2 for the treatment of spinal muscular atrophy

As one of the most serious hereditary neuromuscular disease, spinal muscular atrophy (SMA) is caused by the loss or mutation of survival motor neuron 1 (SMN1) gene. It leads to a decrease in the level of SMN protein and a consequent loss of alpha neurons and progressive muscle atrophy resulting in the progressive muscle weakness, the significant disability and the shortened lifespan. Up till now, only three drugs have been approved for SMA, including the gene therapy drug onasemnogene abeparvovec. The antisense oligonucleotide drug nusinersen and and the small molecule chemical drug risdiplam were briefly introduced. Some representative samples of the small molecule chemical drugs and antisense oligonucleotide drugs targeting SMN2 in the clinical trial or preclinical research phases were also reviewed.