Treatment Advances in Spinal Muscular Atrophy

Nerve and Muscle (L H Weimer, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Nerve and Muscle

Abstract

Purpose of Review

Spinal muscular atrophy (SMA) is a genetic disorder of motor neurons in the anterior horns of the spinal cord and brainstem that results in muscle atrophy and weakness. SMA is an autosomal recessive disease linked to deletions of the SMN1 gene on chromosome 5q. Humans have a duplicate gene (SMN2) whose product can mitigate disease severity, leading to the variability in severity and age of onset of disease, and is therefore a target for drug development.

Recent Findings

Advances in preclinical and clinical trials have paved the way for novel therapeutic options for SMA patients, including many currently in clinical trials. In 2016, the first treatment for SMA has been approved in the USA, an antisense oligonucleotide that increases full-length protein product derived from SMN2.

Summary

The approval of a first treatment for SMA and the rapid advances in clinical trials provide the prospect for multiple approaches to disease modification. There are several other promising therapeutics in different stages of development, based on approaches such as neuroprotection, or gene therapy.

Keywords

Spinal muscular atrophy Clinical trials Gene therapy Natural history Functional biomarkers Newborn screening Standard of care 

References

Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

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Copyright information

© US Government (outside the USA) 2017

Authors and Affiliations

  1. 1.Department of NeurologyChildren’s National Medical CenterWashingtonUSA
  2. 2.Neuromuscular and Neurogenetic Disorders of Childhoood Section (NNDCS)/NINDS/NIHBethesdaUSA
  3. 3.National Center for Advancing Translational Sciences (NCATS)/NIHBethesdaUSA

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