Nusinersen,[7] marketed as Spinraza,[4] is a medication used in treating spinal muscular atrophy (SMA), a rare neuromuscular disorder.

Since the condition it treats is so rare, Nusinersen has so-called "orphan drug" designation in the United States and the European Union.

[4] In 2018, several cases of communicating hydrocephalus in children and adults treated with nusinersen emerged; it remains unclear whether this was drug related.

[10] Spinal muscular atrophy is caused by loss-of-function mutations in the SMN1 gene which codes for survival motor neuron (SMN) protein.

[13][14][15][16] Initial work of target discovery of nusinersen was done by Ravindra N. Singh and co-workers at the University of Massachusetts Medical School funded by Cure SMA.

The trials demonstrated significant improvements in motor function and survival rates among infants with SMA Type 1, underscoring the importance of prompt treatment to achieve optimal clinical outcomes.

[34] In August 2018, the National Institute for Health and Care Excellence (NICE), which weighs the cost-effectiveness of therapies for the NHS in England and Wales, recommended against offering nusinersen to people with SMA.

[36] In May 2019, however, NICE reversed its stance and announced its decision to recommend nusinersen for use across a wide spectrum of SMA for a 5-year period.